My 18is is consuming way to much fuel...

[styles]

Hey guys, so the car is finally back from the mechanic today. It was currently doing 12.2l/100 (before mechanic). Things that were done:
-New control arms
-New bushings
-New wheel bearing for front left wheel
-Lambda sensor got cleaned up and fixed, wasn't working properly
-other sensors all around were "touched up" and overall priming of car

Things he noticed that will need fixing:
Somewhat urgent: front right shock, almost gone
Not so urgent : the catalyzer is getting a bit obstructed, not much right now but still

Also right now the alignment is fucked up, given the work he did.

So... Let's hope the fuel consumption drops! Filled a tank today, will report when I have results!

If your catalytic converter is restricted it will definitely impact your fuel mileage.

[MTD]

If your catalytic converter is restricted it will definitely impact your fuel mileage.

He said it wasn't much, just that he noticed it.

BTW, is there a product maybe to clean it or something, or do I have to get a new one?

[styles]

He said it wasn't much, just that he noticed it.

BTW, is there a product maybe to clean it or something, or do I have to get a new one?

You'll need to replace it.

[MVincken]

How hard is the law about catalysts in your country?
For me it isn´t required to have a catalyst, so i just removed it.
this will free up some horsepower too :)

offcourse you can replace it. but those things are really expensive

[MTD]

How hard is the law about catalysts in your country?
For me it isn´t required to have a catalyst, so i just removed it.
this will free up some horsepower too :)

offcourse you can replace it. but those things are really expensive

they are somewhat hard. What i could is, like my friend did, take of the cat and put a resonator in its place. It disguises it somehow ahah

[MVincken]

or cut it open on the top, remove the catalyst mesh and weld it close again.

but i can´t say if that´s going to affect your engine performance & noise or not

[MTD]

or cut it open on the top, remove the catalyst mesh and weld it close again.

but i can´t say if that´s going to affect your engine performance & noise or not

Well i talked to my mechanic and did just that, its in the exhaust shop as we speak, should be ready today ;)

regarding the fuel consumption, more news... My mechanic used the machine that detects errors in the ocb, and discovered that it was accusing an error that wasn't wiped out previously. So he wiped it all. Let's see if it makes any difference

[styles]

Any update?

Well i talked to my mechanic and did just that, its in the exhaust shop as we speak, should be ready today ;)

regarding the fuel consumption, more news... My mechanic used the machine that detects errors in the ocb, and discovered that it was accusing an error that wasn't wiped out previously. So he wiped it all. Let's see if it makes any difference

[MTD]

Haven't done a full tank since he cleaned the errors from my ocb so I still don't know for sure , but he did it when the other one was halfway through and that one got 10,7l/100. Better, but I still would like to get much better out of a m42..

[MVincken]

any news?

[MTD]

Yeah sorry, i always forget to come back and report.
The fuel comsumption did drop, to 9,8l/100km. Much better, but i still it's too much, for the kind of driving i do (30% city, rest is crusing at 90kph).
I did put on some new 16" wheels after that and the fuel rised to 10,2l/100, don't know why...

I really don't know what to check for, what do you guys recommend?
Furthermore, my next mod is putting a conical air filter, and that should rise the fuel consumption even more right?

[roguetoaster]

Cruising mileage can be impacted by total wheel/tire height. In that respect it's all about revolutions per mile.

A cone filter could actually improve mileage in some cases as it often draws warm air in to the intake versus cold air. Thus a less dense air charge means less fuel injected/less total power. It's all dependent on your specific circumstances of course.

In any case, there's something seriously wrong with your car or engine when an M42 is getting sub 18 MPG. What fuel are you using again, do you carry a lot of stuff in the car regularly?

[sandrune]

Mines doing the same does 260-280 miles on a tank. Only around 20 mpg. A previous owner 4 years ago got around 400 miles on a tank. No clue what's happening.

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[MTD]

Cruising mileage can be impacted by total wheel/tire height. In that respect it's all about revolutions per mile.

A cone filter could actually improve mileage in some cases as it often draws warm air in to the intake versus cold air. Thus a less dense air charge means less fuel injected/less total power. It's all dependent on your specific circumstances of course.

In any case, there's something seriously wrong with your car or engine when an M42 is getting sub 18 MPG. What fuel are you using again, do you carry a lot of stuff in the car regularly?

I think you did the conversion wrong, maybe u used uk mpg or something. But 10 l/100 is 23.5 american mpg.
It still is high anyway. I use 95 octane european gas (don't know exactly what it converts to in "american" octanes, but i think its 91. I don't carry nothing at all in the car, just me and half the time a single passanger. I really can't find whats wrong, plus it's a shame for an engine with just 130000kilometres....

Mines doing the same does 260-280 miles on a tank. Only around 20 mpg. A previous owner 4 years ago got around 400 miles on a tank. No clue what's happening.

Sent from my HTC6535LVW using Tapatalk

Welp, if you do find the problem let me know....

[MVincken]

I think you did the conversion wrong, maybe u used uk mpg or something. But 10 l/100 is 23.5 american mpg.
It still is high anyway. I use 95 octane european gas (don't know exactly what it converts to in "american" octanes, but i think its 91. I don't carry nothing at all in the car, just me and half the time a single passanger. I really can't find whats wrong, plus it's a shame for an engine with just 130000kilometres....




Welp, if you do find the problem let me know....

As far as i know, octane is octane. maybe they have other additives in the US fuel. but in europe you should expect better mileage because of the better fuel.

have you done a compression check on your cilinders?