Hi All,
This is my first post here. I'm from Ireland and have a 1.8 Turbo Audi A4, 2000 reg.
We have a national car test here and my car failed, on it's C02 emissions and electronic throttle control, it wouldn't stay at 2500rpm.
I brought the car to a mechanic who had alook at it and replaced some parts in the turbo, the oxygen sensor, the waste gate regulator valve, top dump valve and bottom dump valve charged me 800euro and the car failed the test again.
I'm major pi**ed off. Was I ripped off?
I bought an engine error code reader and the following codes are showing up, 17536, Long term fuel trim bank 1 system too lean, 17956, Boost pressure control value open.
When the car is running, it doesn't idle over smoothly, and I can feel a slight power drop, like the engine is missing a stroke
Can anyone help me diagnose the problem, please, there is a 750euro fine for driving the car not having passed the National Car Test.
After the amount of money I've spent on it it's really bugging me, because I love the car and when it runs well it's dynamite!
All help will be greatly appreciated.

Ronan

 

Replace the engine coolant temp sensor (can make you run lean or rich w/rough idle if bad) and if that doesnt work a lean code can also point to a bad MAF sensor. Were your codes cleared after the mechanic worked on your turbo etc? Can you clear codes with your code reader??

 

17596 charge pressure control solenoid valve-N75 Open circuit. You may not have an electrical contact to this valve.

 

I replaced the engine coolant temp sensor in a service 2months ago, onepint8tee.
I had a vw golf 1.9tdi auto, before and the MAF went, but the symptoms were, that there was no power at all in it, would it not be the same with the audi?

 

.. i can clear the codes with my reader, and when I do the car runs like a dog for a while until the engine warning light comes on again???
Ahh, that makes sense, crazyhawk, with a new valve the error code still shows!

 

The difference between your VW and the AUdi, is that the TDI is disel <sp> and the audi is gasoline. I am not saying your MAF is wrong, but i wouldnt compare the two with their somptoms too reliably.

 

P1128
17536
Bank 1, mixture adaptation (mult.)

System too lean
- Check oxygen sensor before catalytic converter Page 24-71
- Check oxygen sensor behind catalytic converter Page 24-87
- Check fuel injectors Page 24-38 .
Mult adaptation issue is unlikely a vacuum leak. Other causes could be failing fuel pump or partially clogged injectors. You might want to run some good injector cleaner in the gasoline. It is inexpensive. Make sure that the parts he replaced are connected properly.

P1548
17956
Wastegate bypass regulator valve -N75-

Open circuit
Check the connections at the n75 valve. If the connections are good, take it back to the garage and ask him to fix it again gratis as he obviously put in a faulty valve.