Hi everyone,

I've been working on the old TP for quite some time now, and basically most things are nearly fixed to the point that the car is probably as good, if not better than it was in stock. However, the one thing that isn't better than stock is the fuel consumption, which atm is about 14.8L/100km!!

This is just awful! All the filters have been replaced, injectors cleaned, engine partially rebuilt, new k&n air filter, sparkplugs etc., but 14.8L/100k?? Does anyone else have this kinda economy? coz i know they're supposed to be between 11 - 12 normally.

I just have no idea why it would be so low, as it seems to be about the same nomatter how it's driven. I drive it hard, makes about 420k from a tank. Drive is slow and careful, maybe about 430k. Either way it's not normal I think.. any ideas? :confused:

well my tp's in about the same boat. almost everything mechanically has been replaced and\or renewed. and ive just gotten back from doing a 6500klm road trip and the best i could do was 490klm off a full tank. and thats running it dry and then pulling out the jerry can , just so i could see how many klm i could get out of the tank , oh and thats was all highway driving. so i guess ur gonna have to like it or buy a scooter if ur worried about fuel that much:D

If i use premium unleaded i can get 750kms to a tank in my wagon and that is with the aircon on and loaded up with the wife 3 kids and luggage up to the roofline

sounds like MAF or O2 sensor is dead im on 10-11/100 no matter how hard its driven

start it warm it up and unplug the MAF it should surge while trying to idle to the point it will stall if it doest that it seems to be working. unplug the o2 sensor go for a drive round the block if the proformance is the same as befor i would say thats the problem. also try dissconnecting the battery for 15 min to clear any error codes that may had put your ecu into safe mode default fuel map

Well just today the car ran outa fuel about 50m in front of the petrol station lol, so i know about the best it can get is about 420k from a tank. The oxy sensor was replaced a little while ago, and it seems to work fine. The ECU is returning normal codes, so it doesn't seem to think there's a problem. Coolant temp sensor has also been replaced, and I am thinking of getting a second hand MAF to see if mine is just stuffed. It idles really smooth (sits almost perfectly still, jumping to about +- 25rpm either way too!

I am thinking now maybe the end muffler has collapsed or the CAT converter is blocked.. Hopefully I'll get some time to check it out sometime soon. *sigh* exams next week is gonna suck trying to fix this..


Thanks everyone,
Dave

i know you said that all the filters have been replaced but just making sure the huge fuel filter one was replaced too??

also the maf isnt going to effect your fuel eco THAT much, i mean i havnt been running the maf for the last year before i took it off the road and i never had bad eco

but yes check in to the exhaust, just knock the cat particuly and listen out to her if its collapsed

If i use premium unleaded i can get 750kms to a tank in my wagon and that is with the aircon on and loaded up with the wife 3 kids and luggage up to the roofline

That works out to be 8.2L/100km. Now for a TP 4 cyl Magna, thats exceptional, premium fuel or not, even with only the driver. Are you like driving at 80kph or something? Are you sure you got the standard tank of 62L. Ok, so the wagon has a different tank I think, but its not that much different! The 4 cylinder Magna's using the old Astron engine aren't known for their fuel efficiency.

Driving at 115kph or thereabouts, just you, with one or two overtakings, slight hills, you should expect about 9.7L/100km or thereabouts, which is what I've heard others getting with similar cars. In the city depending on how you drive and conditions etc, you should expect somewhere between 11-14L/100km (I read that somewhere, like carsales.com.au or something). With all new parts you may use slighty less.

Curse Mitsubishi for not having the V6 in the TP, like that did overseas :evil:

Are you sure you got the standard tank of 62L. Ok, so the wagon has a different tank I think, but its not that much different!
well i wouldnt call 10l not much difference :nuts: btw its 64 for sedan 74 for wagon


Driving at 115kph or thereabouts, just you, with one or two overtakings, slight hills, you should expect about 9.7L/100km or thereabouts,
thats still a little high for freeway driving, the fact that i would get average 8L/100km how ever i have heard of people getting as low as 6-7 with the astron

i know you said that all the filters have been replaced but just making sure the huge fuel filter one was replaced too??

Yep I replaced the fuel filter, and despite that change, it doesn't make a whole lot of difference to economy.. it does seem to have changed the mid range performance tho, since now at mid range revs it seems to get a ton more power in it.. it really shows how obviously weak it is in the low range tho, which is a bit annoying.. but i have a feeling something in the exhaust is gone - especially from the weird exhaust noise it just started making. Damn i wish everything would stop breaking down at once :(

well i wouldnt call 10l not much difference :nuts: btw its 64 for sedan 74 for wagon


thats still a little high for freeway driving, the fact that i would get average 8L/100km how ever i have heard of people getting as low as 6-7 with the astron

At what speed do you get 8L/100km? and the others at 6L/100km? For an engine thats notorious as a fuel guzzler thats impressive! Is that stock? If it is they must be very lucky!

I looked at some TP's on Carsguide, but they didn't have fuel economy. Instead I looked up the TR, whose engines have been updated and if anything they use slightly less fuel. Carsguide states that they get 11.5 City, 7.6 Highway. Thats by the 1991 testing standards, not the combined cycle like they use now. Also thats best world scenario, you'd be extremely fortunate to get what cars claim under that testing standard. Thats for a brand new vehicle, not one thats 17 years old. That standard doesn't include other factors such as wind, hills, overtaking, and is done at 100kph. Does anyone know if that testing is done on a track or on a dyno?

My wagon has got a 74lt tank and i usually sit on about 105/110kph on the open road. It works out to be 10lts/100ks which is pretty good considering the full load. When overtaking i can hit 130/140 quite easily with out realising im going that fast. I can travel from the gold coast and my first fuel stop is at Raymond terrece. If i take my l300 4x4 it would have been my 3rd fuel stop.

My wagon has got a 74lt tank and i usually sit on about 105/110kph on the open road. It works out to be 10lts/100ks which is pretty good considering the full load. When overtaking i can hit 130/140 quite easily with out realising im going that fast. I can travel from the gold coast and my first fuel stop is at Raymond terrece. If i take my l300 4x4 it would have been my 3rd fuel stop.

Yeah that sounds about right! About what you'd expect from a wagon full of luggage. Mind you, not having it laden it would still get around 9.5L I reckon! The TP Magna's seem to drive quite well at 130/140, above that the fuel usage goes up.

intersting to see the different fuel use because its an auto maybe? mine is a 5sp man, i noticed since i fixed the vacume leak in my fpr im using a little less fuel too

intersting to see the different fuel use because its an auto maybe? mine is a 5sp man, i noticed since i fixed the vacume leak in my fpr im using a little less fuel too

What mileage are you getting on the highway? I'd suspect yours would be a bit better than normal! :)

At what speed do you get 8L/100km? and the others at 6L/100km? For an engine thats notorious as a fuel guzzler thats impressive! Is that stock? If it is they must be very lucky!

100km set on cruise control, on the 2 lane straight freeway, so never really had to put my food down to overtake, just 2 people in the car with barly any lugage
and when i did the long trips it wasnt stock, as for 6-7L my grandparents when they had a tp wagon years ago chances are they would have been under 100km plus it was a very well looked after motor i have also heard the rare amount of others getting that too


I looked at some TP's on Carsguide, but they didn't have fuel economy. Instead I looked up the TR, whose engines have been updated and if anything they use slightly less fuel. Carsguide states that they get 11.5 City, 7.6 Highway. Thats by the 1991 testing standards, not the combined cycle like they use now. Also thats best world scenario, you'd be extremely fortunate to get what cars claim under that testing standard. Thats for a brand new vehicle, not one thats 17 years old. That standard doesn't include other factors such as wind, hills, overtaking, and is done at 100kph. Does anyone know if that testing is done on a track or on a dyno?
hmm show they make up that figure

this is a manual 2.6 tr for what drive.com say

http://www.drive.com.au/buy/market_value/car_details.asp?nvic=YCB&make=MITSUBISHI&model=MAGNA&series=&year=1993&body=4D+SEDAN

how ever i did notice that the auto was slightly different

http://www.drive.com.au/buy/market_value/car_details.asp?nvic=YCC&make=MITSUBISHI&model=MAGNA&series=&year=1993&body=4D+SEDAN


intersting to see the different fuel use because its an auto maybe? mine is a 5sp man, i noticed since i fixed the vacume leak in my fpr im using a little less fuel too

mm that was the other point i was gonna make chances are there is gonna be a difference between manual and auto due to the ratios

70% of my driving is highway but my fuel usage seems to be about the same v's kms anyways 110 kph is about 2600 rpm for me

The auto I would imagine uses slightly more due to the lossiness of the whole setup really... Anyway I had the exhaust checked, the cat converter is in perfect condition, but both the main muffler and sub muffler had collapsed, and were partially obstructing the outlets. I might also try a new AFM just in case one of the AFM sensors on mine (like temp or pressure sensor) have failed.

I really hope fuel consumption gets better now! :doubt:


Thanks for all the input,
Dave

not to sure about fuel consumption but 40bucks at 115.9?? think it was pushed me over 400k most of it was freeway driving at 3k revs (carbby auto) also was carrying a bit of wait around with it.

I'm doing 9L/100k on my old carby magna TN. I noticed it's most fuel efficient around 2200 rpm (about 90 klm). I did 14L/100k before but then I found out my thermostat was broken and so the choke was always closed.....