On my 1991 TR Magna, I am having a problem with fuel economy. I am getting approximately 320 Kilometers on a full tank of Unleaded Petrol - its about a 64 litre tank.
In spite of the stupidly high petrol prices in victoria (109cents +++ a litre ) I have become more concious of fuel economy.
I know the car is running fine, as I have it regularly serviced. Its definately not a mechanical problem.

Its a 4cyl 2.6 Litre 8 Valve engine. (Astron 2 as well all know :) )
No modifications at all.

I was thinking, next fill up, to put in some Syn Fuel injection cleaner, and fill up with 98 Octane Petrol. You guys think this will fix it up a little? Burn all that junk in the tank.

One last thing, when I put my foot down to overtake, the car has alot of lag before the RPMs start to rise (about .75 seconds?) Is there any way to fix this? Cause sometimes you really need to overtake someone and with that type of lag, its kinda annoying. ESPECIALLY if you got the Air Con on lol.

Thanks peoples.

the lag is probly the auto gear box changing down gears so it rev's in a better range cause you've put your foot down.

in mine (v6 auto) if i put my foot down slowly till WOT it pulls away better and the power transition is fine. no lag no kicks.

and probably getting a EFI clean out will help with the fuel.

Petrol is 112 here in Adelaide.

My car is the same, I floor it and the RPM slowly fills up. Id say it's the auto box.

Strange, I have a TR with a 5spd box and I was gettin 420 on standard rubbish fuel, it gets 530 to a tank on 98 octane, so I stick with that, it'd probably go out to 600 if I didn't rev out to 4500 on take off, but it's fun!

Try looking at things like the catalytic converter, that would kill your fuel economy if that thing is clogged!

I have a TR 4cyl manual. I put 98 octane petrol in it (118c/litre last week :angry: ) and i get almost 600kms from a tank of petrol in mostly city driving. Even with 91 octane id still get atleast 500kms from a tank. So why you are getting 320kms only i dont know...do you have the aircon on constantly or something? :nuts:

I do a hell of alot of small trips though, well under 10k's a day (Uni and back, Saturday Grocery Shopping and out to some club/cofee/lounge etc) Thats pretty much it.

I find i so a hell of alot more K's when I dont do these constant small trips. But still, 320k's vs 500 is a big difference for short trips vs long. :rant:

i found when i had the gay pod filter fitted it also stole about 100kms off a tank of my ultimate 98 octane. check all the lttle things like spark plugs colour etc...

Change your oxygen sensor. They're cheap and the one in there is prob. 10 years old and due for replacement anyhow.

Cut my consumption from 15l/100km to around athe 10l/100km mark.

Can o2 sensors do that? Man Im off to repco. Petrol in Qld is 92-102 cpl for regular And I get 13 litres per 100 city and bout 9 litres per 100 highway ( drivin like a nanny ) Might go to premium though Thanks

That's approximately 20 litres per 100km's which is er abit on the high side.You should be getting about 10-11 litres per 100km's (640 km's out of a tank) .So I reckon you need to get the car checked out to find the cause of the high fuel use and the lag as there could be a number of problems, like blocked filter, injectors,out of tune etc.
My TS V6 SE Magna wagon uses about 9.5 and the KS Verada wagon I also have uses about 9 - 10 but its a manual.
The TP I used to own used 10 liters so that should give you a fair idea how much petrol you should use.

Change your oxygen sensor. They're cheap and the one in there is prob. 10 years old and due for replacement anyhow.

Cut my consumption from 15l/100km to around athe 10l/100km mark.
You beat me to it, i was gonna suggest O2 sensor as well. I cant really say what i get from a tank since i never get close to empty. i dont want to burn the reserve considering the crap thats in it. I usually fill up at 45L of fuel into tank. Usually get 360kms from that since the cars been modded, but used to get 400kms of the same 45L before mods.

Just work it out to L per 100 when u fill up. 9-10 is fairly reasonable.

$2 can of carbi cleaner and reset the ecu wouldnt hurt, on my TP that gets driven hard with K&N replacement filter and a 2.25" cat back & lukey extractors im still getting 9-10ltrs / 100kms, after i got my cat back system my fuel econ went to the dogs 12+ltrs per 100k's untill i reset the ecu, then the week after i done 70k's more over stock exhaust on the same fule now its paying for itself

Interesting read since I've got a stock 2.6 auto TR and I'm only getting around 380-400km per tank. I've also got a lag problem as well.

I'm getting the timing chain changed next week as I know it's near due and I just cant get the car idling right so hopefully that will solve one problem and I'll see what effect that has on fuel economy as well.

After that, a process of elimination as I start to work through the other ideas everyone's put up.

I just chucked premium in my car last week and out of roughly half tank, with occasional air con and mostly all city driving, (cept some freeway work etc) out of a 4 cylinder tr manual... got 240k's... so that aint too bad I guess.

got a 91 TR auto SE (i think) getting bout 400km a tank.. how do u reset the ECU??

might change the O2 sencor aswell form sounds of this thread its pretty heavy on the fuel usuage..

got a 91 TR auto SE (i think) getting bout 400km a tank.. how do u reset the ECU??

disconnect the battery for 15-20 minutes, then connect it back up and drive around for a bit.

or was it d/c it and leave it overnight...?

i forget

I can't get over the crap economy some of you guys get out of your Magnas, you drive pedal to the metal all the time or what? It's worst than the 253 Commodore I once had.

not soooo crap. i get 12-12.5L/100kms with mods but used to get 11L/100kms approximately for an unmodded engine. First problem about the 2.6L is that its a massive 4cylinder and secondly the car is decently heavy and the engine has to work hard to move the car. Compared to other cars its not all bad. It sorta fits somewhere between a regular 6 and a regular 4. Many 4cylinders which are about 2L variety get about 8-9L/100kms and most 6cylinders get between 14-16L/100kms. This is in a comparison of vehicles of similar sort of age of course. Really modern engines are something different alltogether.

Another thing to try (which I've done with a little improvement) is cleaning or changing the air filter. I'm notoriously slack when it comes to that sort of thing and it was chock full of crap :redface:

Quick update on this thread for anyone with fuel economy problems.

I've had the timing chain changed and reset the ECU (disconnect the positive terminal for a while - I left it for 20 minutes). I'm now getting 480 - 500km per full tank of fuel, an inprovement of 100 - 120km per tank.

Next will be to replace the thermostat to see if that's going to help as I think that's a bit suspect.

Quick update on this thread for anyone with fuel economy problems.

I've had the timing chain changed and reset the ECU (disconnect the positive terminal for a while - I left it for 20 minutes). I'm now getting 480 - 500km per full tank of fuel, an inprovement of 100 - 120km per tank.

Next will be to replace the thermostat to see if that's going to help as I think that's a bit suspect.

Your telling me because you reset the ecu & got the timing chain changed that your getting close to 400KMs more?

Did you miss type that?

so if i disconnected the battery for like half an hour, then re-connected this, this should give me better fuel economy?, should i do this just to freshen up the car as i dont think its been reset ever

I cant C how disconnecting the battery would do anything, but then again chickens do lay eggs so I mite do that. I mite use 98 octane fuel aswell instead my economies hit the roof sicne I got my mods. Damn petrol prices. :rant:

to reset the ecu every manual or such i've read says the negative terminal and it shouldn't matter for how long. This is a dodgey way of reseting the computer you could take it into a mitsubishi service department where they use their special tool called a MUT or something and also reset the idle control motor....i was going to do this but i am putting mine on the dyno to find my problem instead...i did reset my ecu the previous way earlier and drove it harsh but i found nothing really changed-i have a fear my ecu could be in a safe mode or something

Quick update on this thread for anyone with fuel economy problems.

I've had the timing chain changed and reset the ECU (disconnect the positive terminal for a while - I left it for 20 minutes). I'm now getting 480 - 500km per full tank of fuel, an inprovement of 100 - 120km per tank.

Next will be to replace the thermostat to see if that's going to help as I think that's a bit suspect.

As if 500k's on a tank. Astron 2's never did that new, especially not after so many years. Unless you drive 90% highway.

I fixed my fuel ecnomomy though, Change spark plugs, fuel filter, cleaned injections and changed air filter. I push around 400 if I do some non 'uni-and-back' (4 k's distance) trips once a day. That really kills my fuel ecnomy to around 330. But yeah, regular unleaded. Gonna go on 98 RON, see how it goes.

i like GTRICE's car, that thing looks slick as

Your telling me because you reset the ecu & got the timing chain changed that your getting close to 400KMs more?

Did you miss type that?

Nah, you misread it :D I said I'm getting me 100 - 120 km more.

As if 500k's on a tank. Astron 2's never did that new, especially not after so many years. Unless you drive 90% highway.

I fixed my fuel ecnomomy though, Change spark plugs, fuel filter, cleaned injections and changed air filter. I push around 400 if I do some non 'uni-and-back' (4 k's distance) trips once a day. That really kills my fuel ecnomy to around 330. But yeah, regular unleaded. Gonna go on 98 RON, see how it goes.

Don't know why that's so unbelievable when there's other figures of 530 and 600 km per tank quoted by others in this thread. :confused: I reckon even with your short trips you should be doing better than 330 though.

When I was running the old Skyline, 3.0 ltr 6 cyl, I was getting an average of 500 km on a 55 litre tank (in both cars it was from Hillarys to Cannington each day in peak hour traffic so no highway driving) so I don't see why I shouldn't expect the TR to give me similar fuel economy.

I drive round quite a bit, some sort of highway but most just around to shops etc (i live on campuss at uni its a bonus :P). But have to travel perth to joondalup couple times week visit gf etc. And on average I be getting round 450-480 roughly a tank on premium.

Don't know why that's so unbelievable when there's other figures of 530 and 600 km per tank quoted by others in this thread. :confused: I reckon even with your short trips you should be doing better than 330 though.

When I was running the old Skyline, 3.0 ltr 6 cyl, I was getting an average of 500 km on a 55 litre tank (in both cars it was from Hillarys to Cannington each day in peak hour traffic so no highway driving) so I don't see why I shouldn't expect the TR to give me similar fuel economy.

One, not much power in the Astron 2 to pull a 1450+ kg car.
Two, Astron 2's suck the fuel out of the tank like it was yesterdays fassion.

Just think its odd as it does mention in various credible websites that City fuel consumption is 13.7 Litres / 100ks'

http://www.mynrma.com.au/magna-tr_mittr_specs.asp

Odd aint it :doubt: Maybe my car is just crap and old, cause It's fricken immaculate engine wise, so yeh. Dix. :P

As if 500k's on a tank. Astron 2's never did that new, especially not after so many years. Unless you drive 90% highway.

I fixed my fuel ecnomomy though, Change spark plugs, fuel filter, cleaned injections and changed air filter. I push around 400 if I do some non 'uni-and-back' (4 k's distance) trips once a day. That really kills my fuel ecnomy to around 330. But yeah, regular unleaded. Gonna go on 98 RON, see how it goes.
Mate i used to get 650kms to a tank, but the last few months been getting 5-550, needs a service and a couple of things done to the engine and she'll be getting that good again no doubt. Thats highway, city will be 5-550 :).

Mate i used to get 650kms to a tank, but the last few months been getting 5-550, needs a service and a couple of things done to the engine and she'll be getting that good again no doubt. Thats highway, city will be 5-550 :).

wtf, i dont know how you get those kind of k's from your car. Firstly ive never heard of Any 2nd gen getting more than 500ks out of a tank on highway/city driving. (unless its straight through freeway cruising)
second, even little pulsars or lasers or the smallest cars in the world dont get 650?!

have u done an electric motor conversion we dont know? lol

wtf, i dont know how you get those kind of k's from your car. Firstly ive never heard of Any 2nd gen getting more than 500ks out of a tank on highway/city driving. (unless its straight through freeway cruising)
second, even little pulsars or lasers or the smallest cars in the world dont get 650?!

have u done an electric motor conversion we dont know? lol
well it was usually around 600, but i did get 650, from a tank of shell optimax, mostly freeway driving. At this point in time i'm at 450 short driving and 5-550 freeway driving, but needs a service like i said and i expect to get to at least around the 550-600 mark. I did notice an increase in fuel economy with my mods though, and my rpm when sitting on the freeway dropped 3-400. But lately it's gone up a little which is why i think my economy isn't as good, but will hopefully go down after service and reco.

A few magnas especially TR"s have had this problem my mates was doing the same thing like 300km from a tank
fuel filter?

i get about 700+ from 65litres with bp ultimate highway driving and around 650-600ish from city
flow mods help the fuel economy too

I love the TR stats from that mynrma website...

0-400metres = 19.3 seconds.. w00t thats fast :bowrofl:

thats for TR Executive Automatic... it then has the

TR SE Manual sedan.. which according to them weighs 25kg's less.. and does the quarter mile in
17.8 Seconds.

hahahhaha yeah i think mine would do about 17ish

i get 400km from 98 octane fuel in my, which consists of only driving peakhour and thashing the hell out of it, ps i have a cat with the substrate rattling around inside. so 650 from a manual driven sensibly isnt to hard to think.

i get 400km from 98 octane fuel in my, which consists of only driving peakhour and thashing the hell out of it, ps i have a cat with the substrate rattling around inside. so 650 from a manual driven sensibly isnt to hard to think.
mines auto!
I just filled up at 100.5 cents and i got only 475km out of the last tank, damn i needa service it really bad. Good to see juice is getting cheaper though.

Well I have TR SE Manual, I always drive sensible.. and I would barely get 500 out of tank..., no mods all complete stock.

Far out, whats up with my car then?

people also need to quote how much they put into the tank when they say how many k's they get. The needle points to empty when about 45L of peddy is used which i usually get about 360kms from or so but the tank actually holds 61L of fuel i think. So someone might say hey i get 400kms from a tank but theyre only putting in the 45L while someone else is saying i get 550kms and is completely draining the tank. comparing k's is only usefull if the amount of fuel being put into the tank is the same.

people also need to quote how much they put into the tank when they say how many k's they get. The needle points to empty when about 45L of peddy is used which i usually get about 360kms from or so but the tank actually holds 61L of fuel i think. So someone might say hey i get 400kms from a tank but theyre only putting in the 45L while someone else is saying i get 550kms and is completely draining the tank. comparing k's is only usefull if the amount of fuel being put into the tank is the same.
Yes i'm talking about the whole tank when i say my kms.

Oh :redface: i meant only to empty sign..

i had a completley full tank, at just under half way, i had traveled approx 220km, so it is reasonable to assume that 400km is the exact figure for this week.

Also how are you guys measuring it? by what the fuel meter says? or by how many litres it takes to fill up? i do the 2nd, then work out a formula and generate the next 5-10L.

Just remember that most fuel meters are decieving, probably on purpose to stop you running out of fuel. i've worked out my meter though, half a tank is half way between 1/4 and 1/2, 1/3 tank is just under the 1/4 sign. dunno how true this is for other people.

I will never go back to regular unleaded anymore. I usually did 430kms off regular unleaded. Now I use premium unleaded and get 530 kms off 1 tank, and a tank for me is only about 58 litres as I leave a bit there. And this is for a manual TR 2.6. This is city driving as well! I usually get about 11 litres per 100km for city driving.

i measure mine by seeing how many litres goin into the tank divided how many k's i did since last fill up ... :confused: (times 100)

sadly .. i do about 12L per 100k .... in highway :( ... with about 15-16L per 100k city driving
this is in a 93 TR GLX (shame :cry: ) which is as stock as a rock

Guys, I just drove Brisbane to Sydney return... you can go a long way in a magna. Mine is a 92 TR Wagon 2.6 5spd. Absolutely stock std. Motor has perfect compression. No heavy load. I usually drive at limit or just above. Not hustling, but not dawdling either.

My figures were:

Leg 1 630k 8.14l/100k (34.6mpg) on 25%ULP + 75% PULP (mostly highway)
Leg 2 632k 8.94l/100k (31.5mpg) on Mobil PULP (includes 150k around Sydney)
Leg 3 704k 8.01l/100k (35.2mpg) on Vortex 98 (all highway)
Leg 4 134k 10.7l/100k (28.5mpg) on Optimax (result skewed cos i really topped up!)

I pretty much drove until the fuel light comes on. When I top up, it is to the nearest dollar after the first auto stop. Theoretically, I could get about 880+ klm from the 71ltr tank if I could stare down the red light, or 1000+ if you could achieve the official figures. How boring would that be!

I was experimenting with PULP and I think the cost is about the same, given slightly better economy (same trip on ULP is 30-32mpg, scuse the old money), but the car is a bit more willing... seemed to rev out a bit easier when asked.

My worst ever figures for were 22mpg, but that pulling a 2m tall trailer, all up cargo of 750kg maybe, into a pretty big head wind. Using 4th not 5th gear to hold 90-100 kph. Never again.

i like GTRICE's car, that thing looks slick as
thank you mate. and....
my sisters ks verada gets about 600km from a tank and it has done 320 thou k's. My magna which is running **** (but i'm getting to it) i still get ok figure 450-500 i dont know ill update you guys...

i use to get arond 400-430 out of a tank in my auto TR if thats any help.. i found it to be a real thirsty bugger

Also how are you guys measuring it? by what the fuel meter says? or by how many litres it takes to fill up? i do the 2nd, then work out a formula and generate the next 5-10L.

Just remember that most fuel meters are decieving, probably on purpose to stop you running out of fuel. i've worked out my meter though, half a tank is half way between 1/4 and 1/2, 1/3 tank is just under the 1/4 sign. dunno how true this is for other people.
so essentially your not using just the fuel tank but the reserve as well which is why your getting more k's.

It sounds like the bigger and more powerful 6's seem to get better fuel economy. WTF :nuts:

It sounds like the bigger and more powerful 6's seem to get better fuel economy. WTF :nuts:

yeaa.. the 2.6 engine is an old design compared to the v6. less efficient.. :cry:

It sounds like the bigger and more powerful 6's seem to get better fuel economy. WTF :nuts:
yeh they generally get pretty close to the same effeciency while the 6 has some 20kw more in the TR/TS v6's. tho what can you expect, they used that type of engine for a long time.

just tried to reset my ecu will see how it goes... had the battery unplugged for over a day was using my rx7 instead.. so just by disconnecting the batteryit resets the ecu?? well its full will record the km on this tank...

'Resetting' the ecu only clears the memory of any errors that the ecu has found. This is straight out of my gregorys manual. Just thought I would clarify this for some people. It does not change anything like the fuel map. It would be wiser to check the self diagnoser for problems, fixing these problems and then resetting the ecu.

yep , i agree, my car using a **** load of fuel, plugged in the diagnostic tool and wadaya know, ecu temp senson was reading constant out of range, replace that and , hey presto, good fuel economy again, ..... then the mods started!!

best 700+km's from 65 litres(70 litre tank) one off long trip on freeway!
worst 280km's( busted ecu temp sensor) ( located under the dashboard guage sensor on the right hand side of the throttle body)
average after mods- 330km's 68 litres 380km's optimax

p.s. vortex is better as it has no detergents in it to clog your fuel system( no it doesn't clean!)

WTF?? is this diagnostic tool, i've only heard mitsubishi has one, doesn't say anything in my haynes (not gregories)....I WANT ONE, where can i get one from?

i think snap-on sell em. they are about $20- $30,000 ( please correct me if im wrong)for a current all model one with adaptors, it plugs into your diag plug above your fuse box under the dash on the drivers side, your gregorys book should show you how to do all of these checks manually!!

here's a thread with some stuff about how to read the problem codes.
http://www.aussiemagna.com/forums/showthread.php?t=18397&highlight=code

i had a look at snap-on and i dunno if this is the exact one but the guys at mitsu had something like this one.
http://buy1.snapon.com/products/diagnostics/MicroSCAN-Scan-Tool.asp?tool=diagnostics&Item_id=65565&PartNo=EESC307B&Price=790&Desc=&SUB_Cat_ID=125628&SUB_Cat_NAME=Scanner%2C+Scanner+Kits+And+Diagnosti c+Cartridges&Cat_ID=125627&Cat_NAME=Diagnostic&group_id=16815&group_NAME=OBDII+Scan+Tools&store=snapon-store&dir=catalog&pix=objects%2F44200%2F44163.JPG&email=true

heres the site with all the tools if anyone wants to browse. http://www.snapondiag.com/

I was gonna post yesterday but having virus/trojan/spyware/worm problems!
Anyway, a dude on the forums was selling a diagnostics cable awhile ago that plugs straight into 2nd gen magna ports. Then leads to a serial plug that goes into a laptop/pc/pocket pc. This was about $100. I was gonna get it but software for pc was hard to find and i dont have a pocket pc :p.

http://buy1.snapon.com/products/diagnostics/solus.asp?linkback=1&partno=EESC310D12&dir=catalog

this was more like the one my mechanic used, p.s. i don't know if the prices are in A$ or US$