Air Flow Meters

[trefor]

Our TT needs a new Air Mass Meter/Air Flow meter or whatever you want to call it today. Getting classic symptoms for a 1.8T engine - boost comes on and the engine gags, power drops off between 3,500 and 4,500rpm, then the power comes back again. Annoying when you're overtaking

Sooo, I remember seeing a website a few months ago that supplies ECUs/AFMs and not much else. Thought I'd give them a try instead of paying Audi £250 + VAT (cough). Anyone remember what the company/site is? Thanks!

[YarisSi]

Isn't it sometimes they just need a clean especially with oil impregnated aftermarket air filters.

[Trefor]

There are no aftermarket parts on our TT, esp. oily air filters.

I took the AMM to bits - nothing to clean either. It's not a hot-wire system. Seems to use some kind of mirror and restricted aperture to measure the air mass/flow from what I can see.

[Mr2Mike]

Trefor said:

There are no aftermarket parts on our TT, esp. oily air filters. I took the AMM to bits - nothing to clean either. It's not a hot-wire system. Seems to use some kind of mirror and restricted aperture to measure the air mass/flow from what I can see.

It probably is a hot wire system, but modern ones don't have a wire as such. They use an conductive element that is printed onto a flat ceramic substrate. Lots of VW/Audi air flow meters seem to have been break recently according to my local garage.

Anyway, www.tuneparts.co.uk stock a wide range of EFI bits, so probably worth giving them a try.

[edc]

Merc Mafa have been tried on some 1.8Ts and they cost a whole lot less. There's some threads on this on www.seatcupra.net

[deltaf]

Trefor said:

There are no aftermarket parts on our TT, esp. oily air filters. I took the AMM to bits - nothing to clean either. It's not a hot-wire system. Seems to use some kind of mirror and restricted aperture to measure the air mass/flow from what I can see.

Called a Karmann Vortex generator. Uses a small aperture to generate air vortexes which get counted by the attached module.
No moving parts...not fixable either if broken...(at least i think it isnt!)

[trefor]

Thanks.

My question is what breaks them? VAG 1.8Ts seem to get through these regularly. I have been told dealers in Germany replace them at the 80k km service by default.

My A6's hasn't gone in 104,000 miles so why did the TT's only last 55,000.

BTW - the car seems fine otherwise, just this power loss midrange so this isn't a major failure, just slightly packing up.

[edc]

Vibration breaks them apparently. They are supposedly so delicate that the metal gril on them is actually there so ppl in the factory don't break it. Oil and filter particulates don't help either.