Guys,

I've noticed that from a standing start acceleration I'm getting a real dead spot in power around the 1500-2500 rpm in my TH Sports. The car will continue to accelerate but it feels dead like it just isn't getting enough fuel or air and I can actually feel a resistance through the accelerator pedal during those rev bands. After about 2600 rpm the power comes on beautifully smooth and like a freight train right up to the red line. Has anybody experirenced similar in a 3rdG auto? Is it an ECU problem or maybe related to the extractors and the onset of the dreaded oxy sensor problems?

Mine is the same & I have been chasing the problem for ages.

I have replaced the central muffler recently with a lukey hotdog (smaller muffler), but that hasnt worked.
I think it is either a break in the flex pipes or the cat is blocked.
Do you get any resonance or rattling between those rpm's ?

After about 2800 the thing is a jet & will rev happily to the redline, but in that rev range it's dead & really stuggles. I have been trying to stay out of that range to get around the problem.

Please let me know if you find the resolution.

:D

Glad to hear I'm not alone! I've fitted a Lukey muffler too, and I'm by no means an expert, but I would have thought that if it was an exhaust problem then it would have affected power delivery right through the rev range, rather than in one particular band?? That's what makes me think it could be ECU related - which will be a pain.

I seem to be having this problem too. I only noticed it after installing my extractors. I have a 3.5 TJ VRX 5 speed man and notice the prob is only around 1500-2500 in second and sometimes third, after 2500 is pulls like a dream.

It only does it sometimes and its generally when its not WOT.

I've got the K&N CAI, and Pacemaker extractors thats pretty much it as far as performance goes...

A quick question.. is there actually a hole in the lower RPM band, or does it accelerate like it did before you fitted the extractors it's just that because there is so much more oomph at the top end that it feels slugish down low?

It feels like the engine is being starved of something during the 1500-2500rpm band when not at full throttle. It doesn't pull as hard and the power delivery isn't as linear as it used to be.

It does however pull a truckload harder up top. Im thinking a retune with a greddy might be beneficial and flatten out power delivery to make it more linear.

I've had the FPR for a while and recently installed Pacemakers. I didn't play with the FPR for the first few days after fitting extractors and it felt a bit sluggish in that area, and then also not as linear through the curve as it was before. I wound the FPR up a bit in a hurry one morning and this seemed to get rid of the problems. I checked a couple of days later what the fuel pressure guage was on and it said about 48PSI at idle (warm). When the car idles at this pressure for a while you can smell fuel, so I wound it back down to about 45. Think it could do with a little more, but its obviously wasting fuel.

With this in mind, I think that a programmable ECU and dynotune is what is needed.

Cheers

Thanks all for your feedback.

Has anyone had their catalytic convertor fail ? What were the symptoms noticed ?

Seems that our problem is affecting modified & unmodified vehicles. Looking at the responses we seem to have modified/altered before & after the cat, so I would be interested if anyone has then changed the cat & if this solved the problem.
:D

Well I'm still running my original cat so this might be the case. but then again my car has only done about 25,000km. So I wouldn't have thought my cat was buggered just yet.

I was wondering if it would be creating a restriction in the exhaust compared to the rest of my system though. Would a high flow cat be benificial in my situation?? I searched through some threads here when I got it fitted and i didn't find too many gains from fitting one. Hence i didn't bother!

It feels like the engine is being starved of something during the 1500-2500rpm band when not at full throttle. It doesn't pull as hard and the power delivery isn't as linear as it used to be.

It does however pull a truckload harder up top. Im thinking a retune with a greddy might be beneficial and flatten out power delivery to make it more linear.
I had the same problem in mine Blake, i removed my pod and put in my stock airbox and filter.. Problem went away..

So myabe with after market mods ( exhaust, headers, CAI.....etc...etc) it would be best to get a piggy back ecu and a dyno!!

So myabe with after market mods ( exhaust, headers, CAI.....etc...etc) it would be best to get a piggy back ecu and a dyno!!
Yeah I think once youve got the above mods you mentioned it time to get a piggyback ecu to really see some good gains across the whole rev ranges.

I find that this happens when I take off when the car is cold. :blah:

It goes, then flattens out, then goes again. :confused:

I had the same problem in mine Blake, i removed my pod and put in my stock airbox and filter.. Problem went away.. I had that problem too when my pod was in too,cept it was kind of pausing between gear changes(auto)panel fixed that up thow:)

I have Extractors, Pod, Full exhaust.

I went to mitsu they struggled to find the problem, Their solution was fuel delivery so they decided to bypass the stock FPR giving it extra PSI, It still happens every now and then, My next option is replacing the FPR and getting a piggyback ECU.

If it all fails I kick the car and see if that works.

Interesting to hear about bypassing the FPR. The dead spot really does feel like the engine is fuel-starved, and I was even considering heading into a Mitsu dealer to see what could be done (and I never like going near Mitsu under normal circumstances!). I would be interested to see if anyone has fixed it using Greddy etc.

I drove a new Nissan Maxima again the other day and realised what totally smooth linear power during acceleration felt like again!

vacuum leaks, unmetered air.

i rekon its a restriction in the intake and the t/b. i noticed on dads old magna (th) that ther was a huge power spot missing, the gtvi has it aswell but not as much as the old th, an easy fix, launch your car constantly at 2500rpm :nuts:

WOW me and my mate have magnas mine is a 1998 magna sports auto his is a 1997 executive. We both had the same problem and we both fixed it. We both had pacemaker extractors and high flow cats what fixed it is i removed my K&N pod filter and he removed his K&N panel filter. That fixed the problem with in 2 days giving the computer time to reset. His got real bad his is a manual and he could not take off at all with out it doing it. Mine started got bad in the morning then got worse and auto tiptronic. But after putting the factory filter back on i have had a power increase and better fuel. I only run vortex gold.

=Distinction=

If you open up your exhaust in anyway (ie new rear muffler, extractors etc) your going to loose bottom end power the more you open it up as your decreasing your backpressure..

An exhaust that doesnt flow aswell will give you less problems down low but will be restrictive when shes starts to rev

The exhaust that on there now is a heaps better flowing than the stock for sure. Well it would want to because it cost me $1,300 :doubt: i got more power then started loosing it with the air filter. Put the old one back on ( glad i kept it ) and it all came back. although i do know what u are say my sister screwed up her Comm because of a dodgy job.

=Distinction=

Bro you might want to look at getting as few other mods. Not sure what your runnin currently. But i have a 98 TF 3.0L V6 and i have big bore exhaust, headers, TB, CAI with K&N pod, plugs and leads, and a Greddy waitin to go in. And i haven't had any dramas with flat spots. I'll check again but i have never felt flat spots. Could be simple things or complicated probs. You say you spent $1300 on an exhaust then this you shouldn't have to worry about. Could be your oxy sensor, your MAF, (with the K&N did you take off the two extra pods on the air intake and plug them with two perfectly fitting water bottle lids????)
Could need a service, change your plugs , leads. Could be a number of things. But i did find that i had a little power loss until i plugged the air intake pods ( pod ran into back of standard air intake which proved useless anyway as wouldn't draw air thru but fixed power loss)

Well, I think I've fixed the dead spot. I took =Distinction='s suggestion, and swapped my K&N panel back to the standard Mitsu air filter, and disconnected the battery to reset the ECU.

I still almost don't believe that such a simple fix could work, but so far the car has accelerated beautifully smooth again, with no hesitation at low RPM and no apparent dead spot. Maybe the K&N was confusing the MAS - I don't know, but it genuinely seems to have worked. Go figure...

so the k/n panel filter looks like to be the pain??? quite weird when its feeding more air in which cools but is ment to gain from aswell....

( instead deadning lower rev and gain up top) :nuts: thats for people with extractors

i've just got k/n and setup, but i cant really feel whether its less or even more if anything spose dyno be the only way....

If you dont know, When changing filter you must reset the ecu, dissconnect the battery for a few minutes, then reconnect it and turn it on, keep it on 2000rpm and leave it there for a minute or too and see if that works

:nuts: Why do we need to? Isn't that the whole idea of the MAS?

Well When buying a new Pod Filter I was told I had todo this so it could adjust to the new settings.

An Ex Mitsu Technician also told me this.

Be mindful too that the Pacemakers have short primaries, designed to give high rpm torque. Longer primaries 600mm+ will give strong low to mid range power and fuel economy. I thought that the FPR was meant to kill the flat spot. Why do I listen to the Forbidden Company :doubt:

A bit of a post script. Have now driven some more since I swapped the K&N panel back to the standard Mitsu air filter, including some country driving. I'm now absolutely convinced it was the cause of the problem. The car now has smooth low down power and torque, while the upper end still kicks-in, thanks to the Pacemakers. It feels like a whole new engine down low again, with a quantum increase in overall drivability. I'm sure there are people who've had no problems with a K&N filter, but it seems to have been the problem all along on my particular vehicle.

Might be the reason for our average figures at the dyno day too!!

What was your A/F Ratio like?

Be mindful :doubt:
The FPR was meant to be used in conjuction with larger injectors/ fuel pump/ and surge tanks. The Forbidden Company thinks that on it's own it should be fine for street cars :nuts:

Yes guys, it's the air filter.

I have a K&N panel on my 3L TF manual and the same problem. I have stock exhaust system, factory engine management.

The dead spot became apparent almost immediately once I put the K&N panel into it.
I thought there might be a slight deterioration in low end tourque, but not as much as there was. I even purchased a brand new paper filter to check. Back to normal.

The panels are not as bad as the pods because they swirl the air past the metering area of the MAS badly. The MAS do not use the whole cross section for metering, unmetered air can pass aound the sensor part and that is REALLY BAD for fuelling... meaning it leans out and detonation under hard revs. If you use a pod, use the special conical shaped one, as that stops the swirling of the air past the MAS, or does it alot less.

These filters are designed for high flow filtering, and for some reason the airflow is 'weird' at low revs. Due to better filter flow and the engine not 'sucking' hard (or straight), the air flows around the MAS. But once the revs rise and it is sucking harder, the problem goes away.
The fuelling gets a bit lean (dyno run proved this to me) but it isn't dangerously lean, or at any high torque point (place most likely for detonation). Makes city driving a pain as well.

But hell, it charges like nothing else from 3000rpm and up!! I'm sticking with the Panel.

Seems the K&N panel is a problem then. I wonder why there hasn't been more people noting in these forums previously?

Since returning to the Mitsu filter, I've enjoyed having the low-down smoothness and power again, even at the expense of a little top end. Previously with the K&N it used to kick-in big-time like a turbo all of a sudden at about 3000-3500 RPM, but I suspect that the feeling was exaggerated by just how totally crappy it was pulling down low. As I do mostly city driving, I was getting tired of the feeble acceleration around town.

Be mindful too that the Pacemakers have short primaries, designed to give high rpm torque. Longer primaries 600mm+ will give strong low to mid range power and fuel economy. I thought that the FPR was meant to kill the flat spot. Why do I listen to the Forbidden Company :doubt:Actually EZ Boy,

Pacemakers give better low end torque than high end..

Reverse what you are saying and youre correct.

Actually EZ Boy,

Pacemakers give better low end torque than high end..

Reverse what you are saying and youre correct.

As allways bain is right lol

I had a dyno done stock and im about to have another one done this week to measure if the K&N CAI kit and Pacemakers are actually doing their job. Hopefully when we compare the curves we should be able to see where i've lost low end torque. But i'll sware i've picked up far more top end than i've lost low down so at the end of the day im much better off.

I've just picked up a Greddy E-Manage which will be tuned early Jan to make the most of these mods and hopefully flatten out the power curve to make it more linear, tune the car to RON 98 and pick up a few extra ponies in the process :D

I'll let you all know how I go.

I'll let you all know how I go.
sweet!

It will give me some kinda idea of what to expect from the greddy when i purchase mine in the new year..

Seems the K&N panel is a problem then. I wonder why there hasn't been more people noting in these forums previously? Very true - but now I think about it I think mine is similar too! (K&N Panel)

Once over 3000rpm, the car really pulls then. It's just getting to 3krpm feels like it's taking it's time.

EDIT: I wonder what K&N have to say about this! Seems like a bit of an issue to me. I'm gonna try my stock filter again now.

The K&N filters do exactly what they are meant to do, flow huge amounts of air with little restriction, and do it very well.

The problem is with the Mass Airflow Sensor, and the fact that Mitsu cut corners when they made them. If someone posts a pic of one I might be able to explain further.

Well how can we fix this then?

Very true - but now I think about it I think mine is similar too! (K&N Panel)

Once over 3000rpm, the car really pulls then. It's just getting to 3krpm feels like it's taking it's time.

EDIT: I wonder what K&N have to say about this! Seems like a bit of an issue to me. I'm gonna try my stock filter again now.
To many people believe an aftermarket filter is better than the standard.. Hence it couldnt be possible that it would downgrade performance!

Fortuntately some people are brave enough to eat humble pie and stick the stock one back in to enjoy the low end gains :)

I buy the K&N filter just for the fact I don't have to buy another air filter again just got to clean this one up every time. But i notice the lag in that 1500 - 2500 rpm area but all i can say my 3.0ltr magna has got some guts for a standard engine once its gets going.

Well how can we fix this then?
Get mitsubishi to make MAF sensors that meter the WHOLE cross-section of the sensor??? :confused:



To many people believe an aftermarket filter is better than the standard.. Hence it couldnt be possible that it would downgrade performance!
It is better, just not down low in the main area where you want the torque for everyday driving...only once the engine (to use a turbo term) is 'on boost' if you know what i mean!



I buy the K&N filter just for the fact I don't have to buy another air filter again just got to clean this one up every time. But i notice the lag in that 1500 - 2500 rpm area but all i can say my 3.0ltr magna has got some guts for a standard engine once its gets going.
Ditto :D

Simple use 2 air boxes, have an rpm activated butterfly valve to switch between the stock filter and the K&N at the appropriate rpm :bowrofl:

But seriouslly I might have a look at modifing the rear section of the air box to see if we can get an even flow over the MAF sensor and see if we can cure this defect :P

I'm really interested to hear from people with a unichip or e-manage about this. Is it just a fueling or timing issue that can be tuned out?

Sounds like there are quite a few ppl with K&N panel filters lying in their garages now....lol

I know it causes i flat spot for a bit...but does it cause any damage? how is it affecting fuel economy?

I know it causes i flat spot for a bit...but does it cause any damage? how is it affecting fuel economy?
I did a dyno run - it gets lean(ish) but there is no detonation. Detonation occurs most readily at the point of maximum torque. The RPM is so low that once they build to a point where some decent torque is starting to build, the problem goes away. I would not be worried about damage at all. The fact that the torque 'comes on' means that the problem is going away with higher RPM. Fuel economy wouldn't be overly affected, maybe a little more. But if you are driving in that rev range most of the time, you need to shift down.... :cool:


I'm really interested to hear from people with a unichip or e-manage about this. Is it just a fueling or timing issue that can be tuned out?
The issue is airflow over the MAF sensor, more precisely the turbulence of the airflow over the MAF/MAS caused by the lack of restriction of the aftermarket filter. This causes more air to be consumed by the engine than the sensor is reporting to fuel management, causing the mixtures to go lean and the engine 'wheezes' a bit with a lack of torque.
You can do two things: smooth out the airflow, or tune the fuel curve to suit, using the Oxygen sensor to work out what the correct amount of fuel would be. I doubt a Unichip would be flexible enough to do what is required. I imagine an e-manage could do a good job, coupled with an experienced tuner and a Dyno.

Maybe you could put a Z32 sensor on it like the Skyline boys do :bowrofl:


Simple use 2 air boxes, have an rpm activated butterfly valve to switch between the stock filter and the K&N at the appropriate rpm
Yes phonic, are you going to use a Supercharger on the stock filter side for more low end boost, then flick onto a Turbo with the K&N for more grunt in the top end????????? :bowrofl:


But seriouslly I might have a look at modifing the rear section of the air box to see if we can get an even flow over the MAF sensor and see if we can cure this defect
I have no idea, maybe there needs to be a plenum between the filter and the MAF/MAS to smooth out the flow a bit....or if you taper the flow from the airbox into the induction hose. I'm wondering what effect the K&N Cold Air Induction kit would have on a car with this problem.
Now I think of it, one of those screens from the Z32 sensors might straighten the airflow a bit.

Well I drove around today with my stock filter reinstalled and it was INSTANTLY noticablity that the flat spot was gone. Was completely smooth again. Higher up it didn't like to rev out as easierly now though, although roads are very wet here atm.

Well I drove around today with my stock filter reinstalled and it was INSTANTLY noticablity that the flat spot was gone. Was completely smooth again. Higher up it didn't like to rev out as easierly now though, although roads are very wet here atm.
Another satisfied customer... :)

I'd still like to use my K&N though! The stock one doesn't "feel" as good higher up.

But having no deadish spot mades driving in traffic a lot more smoother though! Accelleration ~60-80k was more responsive for sure.

No doubt higher RPM won't be as good as the K&N of course, although being so wet today that hasn't been too much of an issue!

have any of you got a power chip put on your machine ??

Hey,

I have a redline panel filter on order for my 2.6L TS Magna with extractors on.
Do you guys reckon it will effect me in the same way? I'm worried that i might be wasting my money on it. I know that i have an older, different engine than you guys, so do you reckon I'll be right?

cheers

Possibly. It depends on the Mass Airflow sensor, if it is the same construction (probably smaller though), then you almost certainly will. Try it and see, then tell the rest of us.

My money is on less torque in the low end. If your airbox is the same as ours (slight possibility) then try and grab a mate's filter and drop it in, go for a gentle 5 km drive, then open the thing up with some hard standing start acceleration.

If you ask me it's fuel.

Have just finished running 2 tanks of Caltex Vortex 98. Flat spot is gone & more torque across the rev range. K&N Panel has stayed in through the process.

Each time I use Optimax I get the drop in power.

Won't be using Shell fuel for a while.

:cool:

If you ask me it's fuel.

Have just finished running 2 tanks of Caltex Vortex 98. Flat spot is gone & more torque across the rev range. K&N Panel has stayed in through the process.

Each time I use Optimax I get the drop in power.

Won't be using Shell fuel for a while.

:cool:
Serious? I didnt notice any difference except maybe a bit smoother with BP ultimate over normal BP unleaded.

I'll have to try that.

I always use normal Shell petrol - and sometimes Optimax

I'm wondering what effect the K&N Cold Air Induction kit would have on a car with this problem.

Blake has the K&N CAI and said above that he is experiencing the exact same problem as the rest of us.... I'll be swapping my K&N Panel over today to test...

Fuels are different, they use different ingredients to produce different results.

The fuel companies blend different compounds that they distill out of the crude oil to make petrol. Petrol isn't just one compound out of the crude oil.

I've heard (from a petrochemist that tests fuels) that Optimax is low in the ingredients that make it torquey (low down). Top end power is usually fairly good. It also very much depends on how fresh the fuel is, if an amount of the volatiles have evaporated away from the liquid, then I don't care if you are running 91 octane unleaded or ELF 120 Racing fuel, performance is gunna be positively fecal.

BP Ultimate is the best (I am told by same petrochemist) for all round, balanced performance.

On my Xmas Holidays, filled up with Vortex (had a Woolworths voucher). Went very well, better torque than Optimax, and seemed to get better fuel economy. And the best thing is, they have now got it in my town! (previously only Optimax available, still waiting for Westoil to get off their asses and deliver the Ultimate here....)

I believe there was an article in ZOOM magazine a while back about different fuels and how they are constructed. If I find it (means digging thru mountains of mags) I will post some more info.

After all this is said however, if your MAF sensor is reporting a different amount of air going into the engine than there actually is, quality of your fuel is the last thing you want to be worried about. It's the fuel quantity to match the airflow that you have to be worried about.

Blake has the K&N CAI and said above that he is experiencing the exact same problem as the rest of us.... I'll be swapping my K&N Panel over today to test...

In conclusion i'm not so sure that there is a dead-sport more that with the K&N filter there is more grunt now after this rev range, what do you reckon?

In conclusion i'm not so sure that there is a dead-sport more that with the K&N filter there is more grunt now after this rev range, what do you reckon?

There is definitely more power 3000+ RPM, the engine seems to take longer to get to that point however. This makes it worse in stop/start city traffic. Open road is fine, mostly. It all comes down to where and how you drive.

It doesn't worry me too much, see signature.

Actually EZ Boy,

Pacemakers give better low end torque than high end..

Reverse what you are saying and youre correct.

Sorry Bain, but the pacemakers and the RPW street and race headers are too short for serious low end torque. For low rpm torque you have to run longer headers with upto 800mm primaries. It's the same with the intake headers. Pipe diameter and length set the scene.

It just is.

The high flow air filter setups will ROB YOU of low end torque because the factory panel is less efficient. That we know. Remember the entire intake pipe is part of the intake header. Intake header length and diameter are CRITICAL to torque generation and are specifically designed and tuned for the vehicles they are fitted to.

FACT: Longer intake (and exhaust for that matter) header primary lengths (ignoring diameter here briefly) produce LOW END TORQUE

Installing a K&N panel or pod removes the inefficiencies of the OE panel and act more as an open ended pipe. Therefore there is less restriction and the air moves SLOWER than when it is sucked through the OE panel. The airflow in the OE panel air intake is faster because it is effected almost entirelt by engine suck, high flow intakes and ram pod setups are less so effected by engine suck - but the performance differences are profound.

Using exhaust header design principles, narrower primaries of longer length have much higher airflow speeds (think of the turbo manifold application here too) than large bore, short primaries. The highflow air filters are inducing a similar effect on the intake as the large bore exhaust primary pipes.

I hope I've communicated this well enough, it all made sense in my head. :D

In my honest opinion, the path to a solution lies in longer header primaries and a flowed throttle body as minimum requirements. Remapped ecu's are a must have.

My AWD has a 3" cat back, cai, K&N fully enclosed pod filter, and t/b with custom headers due within the next 3-4months. Eaton MP90 due Xmas 05.

I have spent 30+ hours researching header and manifold design and spoken with dozens of people, several at 3am in the USA to provide this insight into the problem. For all this I hope it's helpful!!! lol

Interesting Article:
http://www.knfilters.com/massair.htm

I've been reading over a number of different forums this evening and their are plenty of people out there (varying make/models of cars) with K&N filters who claim to be having issues because of dead/dying MAS/MAF sensors that have been contaminated somehow, my guess by either one of two things...

1.) Oil from K&N air filters - possibly over oiled?
(I've recently been informed that when first removed from their packaging, oiled filters should always be left to settle for a little while and then any excess oil should be removed with a lint free cloth before installation into a vehicle)

2.) More dirt/dust possibly passing through the HiFlow filters?
(If they pass more air, why wouldn't they pass more dirt to?)

Perhaps the standard issue paper filters are best for our cars after all? Is shelling out for an expensive HiFlow air filter which may ultimately shorten the life of our MAS/MAF sensors really worth it ... you decide?

Whilst we're on this topic of air filters etc, has it been proved conclusively one way or the other yet if removing the resonators in the standard air intake system is actually beneficial or not?

:think: :think:

Whilst we're on this topic of air filters etc, has it been proved conclusively one way or the other yet if removing the resonators in the standard air intake system is actually beneficial or not?

:think: :think:

Not beneficial. It might look better but it will affect the smoothness of power delivery.

I've just done this to see how it would go and i feel a more responsive throtle as a result. Cant say its all that great in some respects but could definately feel a differance in the throttle.
As for the K&N thing, god only knows as K&N themselves would never admit to it. Imagine the law suits. :badgrin:

Bernoulli's Principle states that as the speed of a moving fluid or gas increases, the pressure within the fluid or gas decreases. (Volume remains constant)
Just food for thought

Interesting Article:
http://www.knfilters.com/massair.htm

I've been reading over a number of different forums this evening and their are plenty of people out there (varying make/models of cars) with K&N filters who claim to be having issues because of dead/dying MAS/MAF sensors that have been contaminated somehow, my guess by either one of two things...

1.) Oil from K&N air filters - possibly over oiled?
(I've recently been informed that when first removed from their packaging, oiled filters should always be left to settle for a little while and then any excess oil should be removed with a lint free cloth before installation into a vehicle)

2.) More dirt/dust possibly passing through the HiFlow filters?
(If they pass more air, why wouldn't they pass more dirt to?)

Perhaps the standard issue paper filters are best for our cars after all? Is shelling out for an expensive HiFlow air filter which may ultimately shorten the life of our MAS/MAF sensors really worth it ... you decide?

So what should we be cleaning the MAS with - If people are convinced that my theory is incorrect :D

So is there a safe way to use an oiled filter??? I mean, can you be *almost* guaranteed you won't kill your sensor if you never over oil the filter????

So what should we be cleaning the MAS with - If people are convinced that my theory is incorrect :D
Take the MAF Sensor out, spray with Air Filter Cleaner Solvent!

Dunno what effect rinsing out with water would have afterwards though, would need to be distilled water, and you may need to dry it out quickly with a hairdryer.

You might be able to use metholated spirits if it shifts the oil.

umm, run out of ideas now...

A contaminated MAF/MAS would not explain the results seen by some members who have simply reverted back to the stock filter to resolve the issue though, ho hum...

We need some certified experts on these forums to provide clear answers on these types of issues dammit! :rant: :rant:

We need some certified experts on these forums to provide clear answers on these types of issues dammit! :rant: :rant:

Don't they drive V8's???

Don't they drive V8's???

nah, they are the "so called" experts ... i mean people who really have a clue. :D

nah, they are the "so called" experts ... i mean people who really have a clue. :D

Touche!

What fun do you get out of walking into a shop and walking out with a 250kw car that you're TOLD will suit every personality and driving style.

Much more fun building to car to suit personality and driving style - then winge when we can't get 250kw natch asp!! :D

I have this problem, but it seems a little more extreme than most cases. My care does it all the time when its cold but in first gear (manual) some times it just wont rev higher or move faster it just stops and then kicks in after a couple of seconds> Are real pain when going through intersections and your car gets blocked of power when you most need it.

My car TE 1996 Manual 3l, only has exhaust and extractors on it, no aftermarket filter. And it happens really bad. Ive always used the same fuel so i doubt it could be fuel, its obviousley not the air filter because mines stock.

The problem has been occuring for a while now and the other day my car broke down because the battery was absoutlley dead. Got that replaced and the problem is there but seems to be less or decreasing. So iam wondering if it has some to do with the ecu reset. I really dont know execpt some of the solutions don't apply to all cases so it must be something else we have figured out yet. Has anyone got a mechanics opinion that knows there magnas well?

I am pretty sure its related to the knock sensor. With a better flowing system the engine will rev quicker ,but since its not in closed loop it doesnt know to supply more fuel , as result it leans out enough to have the knock sensore come one early and retard the timing. Of course running higher octane fuel, more fuel pressure will cure that in certain spots.

I am pretty sure its related to the knock sensor. With a better flowing system the engine will rev quicker ,but since its not in closed loop it doesnt know to supply more fuel , as result it leans out enough to have the knock sensore come one early and retard the timing. Of course running higher octane fuel, more fuel pressure will cure that in certain spots.

I might be insane :nuts: but I thought 3rd gens didn't have a knock sensor, from memory only the 2nd gen's did ... ?

:stoopid:

ok dont shoot me but i do know what im talking about with these cars and the problem that u all experience is a combination of fuel pressure and injectors and the cat.
its all really rank stuff as these cars have a mind of there own.
now the thing that i got when i got a pressure valve put on the transmition i found that this problem went away.
INVECS 2 is the mst anoying thing out. the gear box thinks for u and most of the time is to slow and stuff like that.
when i got my mate to jimmy up this pressure release valve on the box it sort of made the gear box stop doing that stupid thinking thing and walla i have an extreamly linear smooth power band.
only sometimes when i fat the car and it changes up ot may do that dead spot thing but in normal driving it dont.
dont no if that makes sence but there u r.
my two cents worth.

ok dont shoot me but i do know what im talking about with these cars and the problem that u all experience is a combination of fuel pressure and injectors and the cat.
its all really rank stuff as these cars have a mind of there own.
now the thing that i got when i got a pressure valve put on the transmition i found that this problem went away.
INVECS 2 is the mst anoying thing out. the gear box thinks for u and most of the time is to slow and stuff like that.
when i got my mate to jimmy up this pressure release valve on the box it sort of made the gear box stop doing that stupid thinking thing and walla i have an extreamly linear smooth power band.
only sometimes when i fat the car and it changes up ot may do that dead spot thing but in normal driving it dont.
dont no if that makes sence but there u r.
my two cents worth.

People with manual magna's are reporting this or similar problem also athough...

I might be insane :nuts: but I thought 3rd gens didn't have a knock sensor, from memory only the 2nd gen's did ... ?

Youre probably right I was sort of thinking of the second gens and assuming they kept it. Sorry my bad.

I have had the k&N in for a while now and did experience the dead spot, I just recently installed a powerchip and I was VERY impressed, noticeably different! Although there is still a slight dead spot, it is a smaller range and it is less...well annoying - for lack of a better word. Because the overall torque is great. I really expected not to notice much difference, lets just say it was a nice surprise!

So, forget who asked the question, but yes it does improve the problem but does not eliminate it. :doh:

Thanks Rezza, I was hoping that would be the case.....

Quite simple really, extra unmetered air going into the engine needs extra fuel to keep the mixture correct.....

My fuel curve is not 'stock', was flashed by the dealer to try and and cure other problems (see ECU thread that was floating around)

On the dyno with stock air filter it was pretty much stoich right across the board.
But then again that's my car, my experience. Someone else (especially autos - mine is manual) I would expect could have a different experience.

I have had the k&N in for a while now and did experience the dead spot, I just recently installed a powerchip and I was VERY impressed, noticeably different! Although there is still a slight dead spot, it is a smaller range and it is less...well annoying - for lack of a better word. Because the overall torque is great. I really expected not to notice much difference, lets just say it was a nice surprise!

So, forget who asked the question, but yes it does improve the problem but does not eliminate it. :doh:

What power chip did you get?
I have a K&N Panel, pacemakers and VRX muffler (tiptronic gearbox) and have a noticable dead spot.
I have recently installed the GREDDY but am waiting to get it tuned.. i was wondering if reprogramming a greddy would get rid of this flat spot (did you get a greddy?)
has anyone else got the same config who can comment?
Guru

Also do not forget the magan from 1997 to 1999 had 2 software versions avalible for the ecu if u have the 1st one then you may notice low end power loss. i took my TF sports to Mitsu here and they loaded the second version and i got heaps better responce.

Also do not forget the magan from 1997 to 1999 had 2 software versions avalible for the ecu if u have the 1st one then you may notice low end power loss. i took my TF sports to Mitsu here and they loaded the second version and i got heaps better responce.

The man makes a good point. :D

I got a "POWERCHIP" powerchip :nuts: :D
I got the GOLD 98 Chip and it definately helps with the lag...well dead spot!

ok went to and talked to one of the mitsi engineers and yes there is a thing with the power range at that spot. he said its all to do with the resonance of the manifolds and the catalac converters and other metals in the motor.
at 1700 revs it is the worst in the diamante v6 as this is where the pipes hit resonance and this is why there u may be able to hear like a buzz come from your motor.
now he said the only way to over come this is to redesign the whole motor and the outlets and stuff but what they did find and deveop is a computer chip so that in that range it can be slightly lesser felt but thatsonly in the latest models apparently but get a piggy back ecu and this will help alot as well.
its all interesting stuff and i dont understand it much so im aboput to read up on it but this is maybe the reason most of u feel a dead spot.
he also said that some mods will affect the dead spot but a fully stock standard car will have the dead spot there from the resonance within the entire engine

Has anyone with aftermarket cams or any of the Ralliart guys/gals got the deadspot?

I can answer the question on the Ralliart (especially since I started this thread when I still had my TH Sports). I'm happy to say that the Ralliart shows no signs of any flat spot. It simply pulls like a freight train all the way through, and has been a revelation after my Sports. That said, I have no intention of fitting a K&N panel to the Ralliart, and put a new Mitsu paper filter in the other day.

I've had the K&N panel filter in for a week now and I can't for the life of me feel a dead spot anywhere in the rev range. I think I now feel that it revs a little more freely at high rpm but nothing significant.

I've tested it in different gears and paid particular attention between 1500 and 2500 rpm but it feels fine. :confused:

Mitsu claim the Ralliarts develop 90% of their torque from 1500rpm (which is pretty bloody amazing) so it's surprising that fitting a supposedly freer flowing filter would effect the car to the extent that you can feel it.

Something is obviously happening to cause this on some cars and enough people have experienced it for it to be true (unless it's mass hysteria lol ) but I can't think what it could be.


.

I've had the K&N panel filter in for a week now and I can't for the life of me feel a dead spot anywhere in the rev range. I think I now feel that it revs a little more freely at high rpm but nothing significant.

I've tested it in different gears and paid particular attention between 1500 and 2500 rpm but it feels fine. :confused:

Mitsu claim the Ralliarts develop 90% of their torque from 1500rpm (which is pretty bloody amazing) so it's surprising that fitting a supposedly freer flowing filter would effect the car to the extent that you can feel it.

Something is obviously happening to cause this on some cars and enough people have experienced it for it to be true (unless it's mass hysteria lol ) but I can't think what it could be.



.

I'm with you bud (see past posts :) )
Mines a 99 TH wagon 3.5l manual though and I cant really say I've noticed the 'dead spot' at all.
Tried the resonator removal thing too but have put the small one back in to see if I like that better, with regard to the throtle being a little to touchie with em both out.

Got chewing the aft with an RTA inspector at my carwash today and the topic of rpm flat spots came up when he was asking about my car.

He tells me the flat spot is DESIGNED into the car to conform to emissions testing for Australian Compliance, and that if I'm "not happy about it, to get an aftermarket ecu or piggyback and remap that rpm band - Just don't get greedy and get defected doing it" was his helpful advice.

Guess I'll just have to... :D

Can we all move on now??

Sorry i only just read this thread from start to finish.....sooooo

Unless you have something like a powerchip or greddy emanage, having a panel or pod filter isnt really that great....just keep the stock filter in there for now?????

Sorry i only just read this thread from start to finish.....sooooo

Unless you have something like a powerchip or greddy emanage, having a panel or pod filter isnt really that great....just keep the stock filter in there for now?????


Up to you but;

Today I ran my AWD against my Old man's XR6 Ute (manual) and he was only just getting away from me at 120km/hr

My AWD has 3" cat back, 2.5 PEX muffler, custom CAI, custom enclosure for K&N pod filter, tranny cooler and flowed tb.

He had to admit he was SCARED!

Wait 'til the heads, piggy back, shiftkit, headers.....

Cleaning the Mass Air Flow sensor (MAF)
http://www.fordscorpio.co.uk/cleanmaf.htm

MAF Sensor Maintenance
http://spydermagazine.com/2002/March/maf_clean/maf_clean.htm

The bellow link was recently posted in another thread and details the workings of the MAF sensors, i'm posting it here because I believe it's worth the read and it has a great deal of relevance to these and other air-filter type issues:

Making Sense of Engine Air Flow
http://www.wellsmfgcorp.com/counterpoints/Counterpoint3_3.pdf

Getting the Flow of MAF Sensors
http://www.wellsmfgcorp.com/counterpoints/Counterpoint3_2.pdf

...
EDIT: I wonder what K&N have to say about this! Seems like a bit of an issue to me. I'm gonna try my stock filter again now.
I know this is an old thread, but did anyone actually contact K&N, if so, what was the outcome?


PM Travis if you did contact K&N...