2001 - (Y) 100BHP Passat Below Full Power Fault - Diagnosis Help Please!

[daledenby]

My A4 130 TDI has just started doing this,fuel comsumption is OK etc.
What was the outcome of this?

[martin1810]

Always start with a code read. Ask for a complete print out from the ecu, not just codes.

[rjsdavis]

My A4 130 TDI has just started doing this,fuel comsumption is OK etc.
What was the outcome of this?

Hi daledenby

Not sure I'd agree with the code read... most garage's are going to charge you for this!

I got a whizzy bit of advice, which was to disconnect the MAF sensor, and then drive the car to see if it improved the performance. I did, and it did. Made a big difference, so it was immediately obvious that the MAF was mullered.

Had a double-check on it from the garage whilst it was in for a service, and the only code fault's coming up on the snap-on tool were for the MAF. MAF was replaced, and the car was back to normal. Fitted it myself, to save myself an hour's garage labour too....

Easy.

[badade 1.8t]

Hi

It sound like you have the same problem that I had a bit time ago, read the code first will give you a bit understanding where you need to go, in my situation every mechanic was saying need new turbo inc. VW dealer (but not guys here) as I don't have very great experience under the hood I did manage to find a mechanic that was not scare to get his hands dirty and he found split plistic tube from turbo system just under where coolent tank is, trust me don't send or do anything with turbo until you have code and ask about it on here, I was driving like this for about 2 months but this saved me £600+vat for new turbo or recon price

Good Luck

[daledenby]

I had the fault codes read and it came up with 'boost pressure too high'.
The mechanic was almost certain it would be the MAF so he replaced it with one he keeps for testing purposes(he said that he's having to fit around 6 of these a month).The car set off with full power for around 5 seconds then it was back to normal.Obviously it requires further investigation into the problem and i have it booked in for next monday.I'm starting to think its going to cost me a packet.

[martin1810]

daledenby...Find a mechanic that knows what he's doing. Boost pressure too high can't be a faulty MAF. It is nearly always stuck turbo vanes. It can be a falty MAP sensor or MAP valve.

[daledenby]

He thought it was the MAF before the plug in,sorry if my post was misleading.He also said it could be all the things you said too.I just hope that it wont need a new turbo.

[rjsdavis]

He thought it was the MAF before the plug in,sorry if my post was misleading.He also said it could be all the things you said too.I just hope that it wont need a new turbo.

Agree - if you can eliminate the MAF, then this is defo the time where code reading from a good specialist that knows VAG cars well will come in handy. I'm very fortunate insofar that the garage that looks after my car is a personal friend, and I know i'm not getting stiffed, or getting billed for diagnosis time of the computer which I appreciate many garage's earn quite a few quid from doing....

Tread carefully. Defo take a garage recommendation in your local area if you can. Would be worth travelling to get to some one good and reliable!

[daledenby]

The car went in today and the mechanic found that a wire to the boost solenoid had broken so it was an easy fix but it took a while to find.The cost was £80 including the original scan that he did.

[rjsdavis]

The car went in today and the mechanic found that a wire to the boost solenoid had broken so it was an easy fix but it took a while to find.The cost was £80 including the original scan that he did.

Cool - that sounds like a decent mechanic, and so nice that he didn't appear to stiff you to fix.....