I can sure use some. My daughters Manua 97' l A4, 2.8Q accelerates fine, but when stopping or at idle, it will suddenly, and without warning drop the rpm and stall. Checked alternator, battery, and ground all are ok. Does anyond have any suggestions as to what the possible causes are? Thanks in advance for your input.

tjcinco

 

First thing... make sure engine idle speed is at the recommended RPM. If it is too low, engine might stall at times. If it is too high, then it just use more fuel when idling.
FYI... a little higher idle speed can help a newbie learn the stick on weaker engines (abt 100hp?).
It will help prevent engine stall at start ups but 150hp enigne doesn't really need that.
You can adjust that easily yourself but it is up to you.

also check
.. air filter, air sensor
.. make sure spark plugs are tight enough (i hav seen lots of cars with loose spark plugs)
.. vaccum and compression

I might also check the distributor.
i am not quite sure 2.8 use the distributor or the Iginition Control Module (ICM).
I know for sure that 1.8T uses ICM 'cause I had it replaced about 3 weeks ago. (it cost a lot)

Hope that helps