Clean your Air Mass Sensor !!!!!

**james946** · 15-06-2009,01:46 PM

i know this is going to sound like a stupid question, but where abouts would i be able to get that done? is this expensive?

**Crasher** · 15-06-2009,01:49 PM

Not stupid at all, a relevant question. Any decent well equipped garage should be able to carry out an engine fault code scan for you and this should cost around £30. Make sure you get a printed out code report and that the stored codes are cleared.

**JezzaL** · 17-06-2009,06:33 PM

Originally Posted by Killerwhat?

Hello everyone I'm a Forum newb!

Do any of these sound familiar:

Unstable idle
Hesitation between gear changes
Flat spots
Engine speeds up when you lift off - yes really !
Throttle 'hangs' between changes
Missfire above 4000

Well. I've scoured the forums for something definitive on all the above which have plagued my s/h (125 k) A6 1.8T Avant (petrol) since I bought it a year ago. So I finally bit the bullet, took out its Air Mass Sensor (often referred to as the MAF) and cleaned it.

What a transformation

, it finally feels like the car I always thought it should have been !

Want to know how ? reply to this thread, it took me about an hour.

Cheers !

Please share what you did with me. I have the same problem. Managed to take out the sensor part, but can see no residue or anything. thanks.

**P4ulyt** · 27-06-2009,11:07 AM

hi Steve

i've got what appears to be a similar problem, first started after a monsoon drive back from wales and then intermittently since then. thought it might be one of the coils as i've replaced 2 in the laet 18mths but it does get better occasionally. where is it and do you think it sounds like the air mass sensor? if so how do i clean it or exchange it myself? too busy for garage trips at the moment.

thanks Paul

**Crasher** · 27-06-2009,11:37 AM

Water ingress into the AMM can be a problem on the Passat and A4 but not on one as late as your 2004 so I would suggest an Audi dealer supplied exchange AMM as a starting point.

**P4ulyt** · 27-06-2009,12:47 PM

hi, just drove it again, emissions light flashing at me, drove straight to audi dealer as it now feels like a coil (happened before and it is burned in my memory) bought a new coil, fitted it and is running well now. maybe the coil was grumbling for a while. all i've got to do now is to get rid of the warning light which as i was driving back is now on permanently. do you think this will go out by itself if i do a longish drive? does it reset itself once all is well? car appears to be cured (fingers crossed) as i need it this weekend.

thanks Paul

**Crasher** · 27-06-2009,12:58 PM

I think it may go out one day but it could be weeks.

**henlowstu** · 23-07-2009,06:39 PM

Getting the usual reving and loss of power problems. Points to MAF but unsure where it is. The only sensor i can see in line with the airflow is caked in oil! Have taken pics of suspected location and of the mucky sensor so any advice/confirmation plus what to clean with would be very helpful.GetAttachment1.aspx.jpg

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**Crasher** · 23-07-2009,07:40 PM

That is the MAP/IAT (VW call it a “Thrust sensor”) sensor which sends the ECU the boost pressure and the charge air temperature. These do stick but cleaning them is pointless. The Air Mass Meter (what people call the MAF) is on the air filter housing.

**henlowstu** · 23-07-2009,08:10 PM

Thanks for that. Never really had much need to look under the bonnet as its been so reliable. Not much room in there!! Take it air filter housing on the left had side behind heat shield. Have tried to email the chap that did the initial thread but no response yet!