poor fuel economy

[T2Andy]

Does 17-19 mpg sound normal because i cant better this ,my problem is the car is running
very rich ,the exhaust is realy sooty and the performance isnt what it was.ive changed the lambdor and cleaned the fuel system and injectors with FORTE .The temp stays between 50\90 ,so would thermostat cause over fueling to this degree .The revs rise and fall quite a bit and sometimes cuts out

[Chris M]

You cleaned the MAF too mate?

[T2Andy]

Hi Chris yes about 6 months ago.

[Azman]

Scuse the being thick. How do you clean the MAF?

[Chris M]

You can use IPA to clean the MAF out with, or i sometimes use a good brake cleaner and make sure the element is clean and free of cr@p. Plenty of good methods on here.

Vonbeck has made his own MAF Bath

HTH

[newsh]

Scuse the being thick. How do you clean the MAF?

Put it in a MAF BAF

[T2Andy]

you have to clean the thin wire inside with IPA alcohol.do a search lots of info on here.

[dan_b]

@Andy - I am getting EXACTLY the same as you at the moment - the car is clearly running rich as I'm getting a bit of sooty exhaust on the overrun/ high boost gearchanges, my economy is down to the low 17s and the exhaust pops like mad at the moment, which is actually quite fun, but it does give some indication of how much unburnt fuel is getting thrown down the pipe! I'm using Tesco99 or Sainsburys 98 and have also recently run through a couple of bottles of Millers CVL Turbo to try and see if that would help. Oh and I've also changed the fuel filter. Like you I've recently cleaned the MAF, my lambda is less than 12 months old as, are my sparkies. My temperature is fine though. Would appreciate a steer on this one!

[Jamo]

I wouldn't mind a heads up on this.

I've found that i have to use a tank of unleaded 1 in 5 for using optimax to get decent mpg.

I put some in today and got 24-25 mpg to stanford hall and back.

[neebover]

Does 17-19 mpg sound normal because i cant better this ,my problem is the car is running
very rich ,the exhaust is realy sooty and the performance isnt what it was.ive changed the lambdor and cleaned the fuel system and injectors with FORTE .The temp stays between 50\90 ,so would thermostat cause over fueling to this degree .The revs rise and fall quite a bit and sometimes cuts out

Hi,

I had mine cutting out and wouldn't idle, had it code read and my MAF was faulty. Got a new one and running great since.. It was cleaned first also to no avail!!

Chris

[Knight Rider S4]

I get 19 at the mo didnt think that was to bad with MODs ..what is everybody else getting...if i was getting 22-25 i would have to drive like a minister

[neebover]

I get 19 at the mo didnt think that was to bad with MODs ..what is everybody else getting...if i was getting 22-25 i would have to drive like a minister

I last reset my ave mpg about 750 miles ago.. currently getting 24.4 mpg, use Tesco 97 Ron (don't have 99 up here), don't drive like a minister that often either!!

[Audi Parts Guru]

Ive changed the lambdor and cleaned the fuel system and injectors with FORTE

The only way to properly clean injectors is by ultrasonic cleaning and flow testing. The "bottles" of so called injector cleaner that you buy in Halfords and most petrol stations are basically crap and a waste of money. Just ask yourself this question, how can you clean something that you can't see?

[T2Andy]

Yes i understand what your saying and having the injectors cleaned properly is on my list of things to do ,but ive also herd good reports on FORTE cleaners ,thought id give em a go for the price ,i guess mine could be dribbling .Do you think the thermostat is the main reason for over fueling.

[neebover]

Yes i understand what your saying and having the injectors cleaned properly is on my list of things to do ,but ive also herd good reports on FORTE cleaners ,thought id give em a go for the price ,i guess mine could be dribbling .Do you think the thermostat is the main reason for over fueling.

I have had 2 lots of Forte Gas treatment from my local Audi garage. Found running was improved and that's when my mpg improved also. Obviously the new MAF solved all problems.. Doesn't sound like thermostat.. get your car code read.. MAF will prob show as faulty..