ffwjgross

I have a 1998 A4 1.8T ATQ, AEB engine with low power. (Also measuring no turbo boost.)

In ross-tech shareware, the engine module reports throttle angles up to 86 deg. and the Operational Status field never shows "Full" even at WOT.

The AT module does show 100% throttle.

Does the throttle body adapation compensate for this (so 86 deg = WOT) or do I need a new TB?
I swaped in a different used TB and it reads the about same values.

myers1.8TQ

Are you asking why you have low power/ no boost.

ffwjgross

The goal is to get my power back
Wondering if I really need to replace the Throttle Body. I hope that would give me some of the power back.

I was maybe going to do another thread on the turbo after some more checking on my end.
I think I need to check to see if the turbo is turning. Diverter Valve diaphram leaks, but seals boost air closed. I feel no turbo anything at all, but I havn't driven the car in years. The wastegate is free. I'm showing a least a 1/4 inch vacuum at the intake manifold always.

Thx. Any Ideas?

ffwjgross

Re: Ross-tech Throttle angle reported (for my post TB=Throttle Body)

k1.8t

you need to start off by trying to adapt the throttle body to the ecu. i would clean the throttle body and install it with a NEW gasket. try re-adapting it to the ecu after you clean it. if it shows an error message in channel 4 after you cleaned it, odds are the throttle body is bad. as for the diverter valve, the condition of the DV can cause the car to overboost. in turn, the ecu will pull the timing out so far that it feels like you have no power. i strongly recommend pulling the turbo inlet pipe off and checking to make sure the compressor turns freely. good luck. i will answer any other questions you may have

ffwjgross

You mean clean the throttle body with carb. cleaner so it physically open up easier or clean the electronics inside?

Unfortunately (turbo $) I think I don't have an over boost problem, I never measured any boost ever... I will replace the diverter valve too once I check the turbo.

Thanks, I'll do what you suggested in a few days.

k1.8t

yes carb cleaner. do not open the electrical portion. open the butterfly and clean the lines of carbon stuck around the butterfly when it is in the closed position. make sure it is completely spotless.

ScratchRob13

That is drive by cable, you need to do a manual TB adjustment. its in the bentley manual.