Hi all,

The saga continues with my car having some unexplainable problems. I've read up about many of them and followed some different advice to try and see if I can find the cause.

Problems:
- It shudders at 2000-3500 rpm during any acceleration.
- Car has a very rough idle on petrol both when warm and cold. Idle is around 200-300rpm and engine seems to splutter. Does stall sometimes. Lpg is fairly good idle but still fairly low at 500rpm.
- Strange hissing noise during idle, sometimes it rattles.
- Car is very hard to start - needs at least 8-10 cranks. Sometimes refuses to start. Warm starts seem to be worse than cold.
- Very odd issue on petrol when accelerating; After some time idling - car seems to loose 90% of power until 2000rpm. Foot to floor from start and it barely launches off line. Come 2000rpm - engine feels like it "turns on" and all power is released.

Work done to try and solve problems:
- Wheel bearings checked. Loose drivers side wheel bearing. Replaced with good 2nd hand unit (stock will have new one pressed in soon). Pass side bearing fine.
- Intermediate shaft bearing found to not spin freely - replaced.
- Wishbone ball joints checked for signs of damage. None found.
- Spark plug leads changed from NGK back to genuine mitsy's. No change - seems to have done more harm than good.
- Spark plugs checked. IridiumIX's installed 40,000kms ago. They are used, but in good condition.
- ISC replaced with 2nd hand unit. No change.
- TPS readjusted to mitsy manual intructions.
- EGR solenoids replaced with 2nd hand unit. No change. Power disconnected and reconnected during testing.
- EGR to Throttle body vac lines checked for leaks by spraying carby cleaner. No change in rough idle. Vac lines disconnected from solenoids and directly connected to tb. Again - no change.
- EGR valve on front rocker cover checked and cleaned. Was making a clicking noise before being replaced.
- Dizzy dismantelled and checked. No signs of wear or rust. Back of dizzy has got a bit of oil on it.
- Rear exhaust to intake manifold pipe has a gasket that is missing. No air leaks found though.


Does anyone have any idea what could be causing these issues? It's driving me insane and it's getting really hard to drive this car.

It's going to be sent to a mechanic very soon, but I was hoping for some direction on what to expect or at least provide some pointers to the mechanic. He is someone who did his apprenticeship at Mitsubishi during the early 2000s but not a magna specialist.

Thanks heaps! S.O.S!

Have you tried cleaning your MAF sensor with MAF cleaner (eg. CRC Mass Air Flow Sensor cleaner, available from Repco), and the connector with contact cleaner?

Have you tried cleaning your MAF sensor with MAF cleaner (eg. CRC Mass Air Flow Sensor cleaner, available from Repco), and the connector with contact cleaner?

Thanks for the quick reply! :)

Nope, I have not actually. I'll go to repco and buy a bottle.

Surely a dirty maf sensor would not cause so much issues?

Worth replacing?

Can you get any sense of whether the engine might be running lean (spark plug colour indication maybe?) Seems to me a small leak in the intake plumbing between the MAF and TB could give you the hiss (which gets lost in the noise at higher RPM) and some of your other performance related issues. Other things that I've seen mentioned as causing somewhat similar symptoms in some circumstances are the ignition coil (usually more problematic with rising temperature) and the oxygen sensor (though this usually has symptoms of running rich). I'm also only speculating that a dodgy fuel pressure regulator might also give some of your symptoms (especially if lean running is identified), but I've not seen much written about this (they seem quite reliable).

Surely a dirty maf sensor would not cause so much issues?

Given the way Mitsu MAFs work, anything that can disturb their operation will result in faulty airflow signalling to the ECU. A big buildup of crud can do that, although the air filter should minimise this. Be careful in using the MAF cleaner; from what I've read ham-fisted cleaning can damage them.


Worth replacing?

If you have a spare handy, swapping it might be diagnostically useful.

Thanks for the quick reply! :)

Nope, I have not actually. I'll go to repco and buy a bottle.

Surely a dirty maf sensor would not cause so much issues?

Worth replacing?

It can cause rough running and stalling, I'd say its worth at least cleaning it.

Stuffed MAF sensor can cause a whole range of issues. In my case it caused the EGR valve to open when it shouldn't, causing a lean mixture and shite acceleration/stalling when taking off. My situation was different however as idle was not affected. I'm not convinced that a damaged or dirty MAF would cause idling problems, however picking one up from a wrecker (eg. Mal) wouldn't be a bad idea, possibly there is more than one thing wrong. Easy replacement, especially if you grab the whole intake pipe. The valve to the left of the front valve cover is the PCV valve, rattling is not an indicator of stuffed-ness (new ones rattle). If not already replaced, Repco do them $$$ cheaper than OEM (about $15 from memory). It's basically a one-way valve, you should be able to suck air through it but not blow. The EGR valve, if fitted to your model, is over the back of the plenum chamber, near the throttle body, and it has a diaphragm on top operated by a vac line. Inside is a piston valve, if this is stuck open it could cause the problems you have. It's easy to remove and check if the valve is closing fully and operating smoothly, giving it a clean or replacing might help (it's possible that it only sticks when hot, or sticks more when hot).

Can you get any sense of whether the engine might be running lean (spark plug colour indication maybe?) Seems to me a small leak in the intake plumbing between the MAF and TB could give you the hiss (which gets lost in the noise at higher RPM) and some of your other performance related issues. Other things that I've seen mentioned as causing somewhat similar symptoms in some circumstances are the ignition coil (usually more problematic with rising temperature) and the oxygen sensor (though this usually has symptoms of running rich). I'm also only speculating that a dodgy fuel pressure regulator might also give some of your symptoms (especially if lean running is identified), but I've not seen much written about this (they seem quite reliable).

Thanks heaps for all that info and suggestions!

I'll need to find out a way to check if the engine is running lean. The exhaust doesn't show any signs of running excessively lean, but doesn't mean the engine is running lean - esp with the low idle and lack of low down power.

With the intake plumbing - I actually replaced that section a week ago, because my old one had creases and splits around where the pipe meets the mixer. Replacement piping is from a pre-TJ model so it has two resonators (one ontop and underneath). The bottom reasonator didn't clear the charcoal canister so I blocked it with a very tight fitting bottle cap! I can't see & feel any leaks, but I might need to spray down the area with some water to see if I can find any bubbles from an air leak. I'll get a spare maf & intake pipe from the wreckers.

Where would the ignition coil be? How could I test if that is the problem?

Oxygen sensor was replaced with a one from ebay less than 5,000kms ago. (http://www.ebay.com.au/itm/OEM-QUALITY-MITSUBISHI-Magna-TR-TS-TE-TF-TH-TJ-Pajero-Verada-Oxygen-Sensor-O2-/121185231974?pt=AU_Car_Parts_Accessories&hash=item1c3733e466)

The fuel pressure regulator could be faulty since the car has spent 70% of the last 40,000kms on lpg. Might get anouther 2nd hand to test. If it fixes the issues, then I'll buy a new one.

Thanks again to the both of you for your help!

Thanks heaps for all that info and suggestions!

Where would the ignition coil be? How could I test if that is the problem?


Ignition coil is part of the distributor, if I'm not mistaken

Stuffed MAF sensor can cause a whole range of issues. In my case it caused the EGR valve to open when it shouldn't, causing a lean mixture and shite acceleration/stalling when taking off. My situation was different however as idle was not affected. I'm not convinced that a damaged or dirty MAF would cause idling problems, however picking one up from a wrecker (eg. Mal) wouldn't be a bad idea, possibly there is more than one thing wrong. Easy replacement, especially if you grab the whole intake pipe. The valve to the left of the front valve cover is the PCV valve, rattling is not an indicator of stuffed-ness (new ones rattle). If not already replaced, Repco do them $$$ cheaper than OEM (about $15 from memory). It's basically a one-way valve, you should be able to suck air through it but not blow. The EGR valve, if fitted to your model, is over the back of the plenum chamber, near the throttle body, and it has a diaphragm on top operated by a vac line. Inside is a piston valve, if this is stuck open it could cause the problems you have. It's easy to remove and check if the valve is closing fully and operating smoothly, giving it a clean or replacing might help (it's possible that it only sticks when hot, or sticks more when hot).



It can cause rough running and stalling, I'd say its worth at least cleaning it.


Given the way Mitsu MAFs work, anything that can disturb their operation will result in faulty airflow signalling to the ECU. A big buildup of crud can do that, although the air filter should minimise this. Be careful in using the MAF cleaner; from what I've read ham-fisted cleaning can damage them.

If you have a spare handy, swapping it might be diagnostically useful.

Air filter was also replaced last week. Clean as a whistle.

Seems the maf needs to be given some attention. I've never cleaned it and I've had the air filter off countless times so it could've easily got dirty. I'll clean it and pick up a 2nd one from the wreckers to use for dianosing if that is the issue.

I have disconnected the maf sensor while the engine was running, and the rpm dropped even lower.

I'll also check out the two EGR valves for its flow. Is the rear one attached to the intake plenum - and faces towards the firewall?

Ignition coil is part of the distributor, if I'm not mistaken

You are not.

I'll also check out the two EGR valves for its flow. Is the rear one attached to the intake plenum - and faces towards the firewall?

Only one EGR (exhaust gas recirculation) and yes, it is on the back of the plenum close to the firewall. Reading your problems again my money would be on the coil I reckon, not sure how to test it but if it's the problem it is easier to replace the whole distributor, with new cap & rotor button.

I don't know this model but here goes. Some thoughts.

- Very odd issue on petrol when accelerating; After some time idling - car seems to loose 90% of power until 2000rpm. Foot to floor from start and it barely launches off line. Come 2000rpm - engine feels like it "turns on" and all power is released.

Have you noticed any smoke. Blue or black smoke?

Also with all the things you have checked, have you looked at the fuel filter?

Although when you say a sucking sound, it does sound like an air leak somewhere in the intake. Also I would use penetrating oil rather than water to check for leaks, the engine will still faulter if there is a leak but the idea of spraying water...
To each their own I guess.

swap out dissy for a working one. bet it is the coil pack. the hotter a coil pack gets, the less spark it creates. therefore, worse on hot starts.

Thanks again everyone for all your help!


Only one EGR (exhaust gas recirculation) and yes, it is on the back of the plenum close to the firewall. Reading your problems again my money would be on the coil I reckon, not sure how to test it but if it's the problem it is easier to replace the whole distributor, with new cap & rotor button.

I'll check both EGR valves nonetheless. I know they can cause some issues.


I don't know this model but here goes. Some thoughts.

Have you noticed any smoke. Blue or black smoke?

Also with all the things you have checked, have you looked at the fuel filter?

Although when you say a sucking sound, it does sound like an air leak somewhere in the intake. Also I would use penetrating oil rather than water to check for leaks, the engine will still faulter if there is a leak but the idea of spraying water...
To each their own I guess.

I've not looked back towards the exhaust during the period at which the odd acceleration happens. I'm more focused on trying to get the car moving! I do check my mirrors very often and I've not noticed any lingering smoke. Starting or normal running of the engine does no render any smoke at all.

I will try penetrating oil instead - something like WD40 or RP7?
My preference would be carby/throttle body cleaner but I am just being mindful of putting explosive chemicals near a potentially very hot engine. I figured with water that if it near the leak, then bubbles may form or if it get sucked into the engine, then it'll splutter a bit.

The fuel filter was replaced about 2,000kms ago with a Ryco one. A few months ago, I had issues with the car refusing to start. After changing the battery and the fuel filter plus undoing the fuel piping to release the gunk in the lines, the car started and has been running ever since. Doubt the filter is a problem but will check the area for any potential leaks it might have. Might be worth conducting a test on the petrol pump.


swap out dissy for a working one. bet it is the coil pack. the hotter a coil pack gets, the less spark it creates. therefore, worse on hot starts.

I've got a spare dizzy that was originally in my car. Some time ago it caused me some minor idling problems and I replaced with my current one. Probably not worth putting back into the car. Dizzy's are not cheap! Even crappy 2nd ones are $80. New they seem to start at $250 :(

I wouldn't spray carby cleaner anywhere near a hot engine.
WD or RP is fine.
"I'm more focused on trying to get the car moving! "

Well that might be the clue.
Fuel or spark.
It could be bogging down from being too rich or too lean. The sucking sound is a worry.
Or it could be an ignition problem. As in the timing retarding through a loose connection, or as a long shot,
a short in the loom to earth.

I'm sure other mechs here will help.

*cough*takeittoaproyoucheapgypsybastatd!*cough*

Ahem, excuse me

Just a fyi for anyone who needs a new dizzy - mitsubishi asks $1550 !! I could buy a 3rd gen for that price! LOL lol :wtf

I wouldn't spray carby cleaner anywhere near a hot engine.
WD or RP is fine.
"I'm more focused on trying to get the car moving! "

Well that might be the clue.
Fuel or spark.
It could be bogging down from being too rich or too lean. The sucking sound is a worry.
Or it could be an ignition problem. As in the timing retarding through a loose connection, or as a long shot,
a short in the loom to earth.

I'm sure other mechs here will help.

Ill spray down the hoses with wd/rp and see if I can find a leak.

If anything, Id imagine the engine would be running,lean. In the older days it was easily adjustable but the advent of ecus makes this difficult.

Ill try to see if I can "borrow" a working dizzy to test before i throw $300 for an aftermarket one. It would explain why the car is now so hard to start. No doubt starter motor and/or wiring couldve carked it.

At this stage, ill be lookibg at cleaning and potentially replacing the maf sensor and replacing the dizzy/ignition coil.

Well the saga continues.

Car now refuses to start on petrol and hard starts on lpg. Even if I switch to petrol, it'll stall pretty much stall straight away. Does run fine on lpg apart from the rough idle.

I changed the distributor this weekend to a 2nd hand 3L one and there's no change in behaviour. If there was some change I'd look at the distributor as a potential part of the problem(s) but I think we can rule it out as the spare one behaved exactly the same as before.

I can confirm the fuel pump does sound like it works. I had someone start the car while I did the "screw driver to the ear" trick. Definitely can hear the fuel pump buzzing away during ignition and when the car started on lpg.

I'm thinking that maybe the injectors or fuel pump is blocked. It wouldn't explain why the car has a rough idle or shudders, but if the line to the engine was blocked, then it'd go some way to explaining why the car doesn't start on petrol and hard starts on lpg.
I will pull out the injectors this week and get my mate to sonify them.

Any other suggestions on what could be the cause?

I see you've replaced the distributor, but have you swapped out the MAF yet?