Previously my 1.8t wagon has had a rock solid idle at 800 RPM, just recently it has fluctuaded between 600 and 1000, the only thing I have done recently to the car is change the battery. Does need to 'learn' again and this will stop with time or is it something else?

I do not not have an answer, but I have the exact same problem. Changed battery, then got variable low idle in nuetral or park. When in gear and stopped, engine stalls. Have you had any luck solving this problem?

Thanks

Dear both,

I have run into the exact same problem with the engine revving low in drive at stopped at a light, etc, it will stall. This just started after replacing the battery. Have either of you tried to put the old battery back? I was also wondering if something was "unlearned" when the battery was disconnected. Any help is greatlt appreciated.

see followinglink which describes this exact problem for starting passats with low/dead battery
http://www.volksparts.com/ttps.htm
I now need to find info on "Throttle body adaptaion" which is part of the prescribed fix. Any help would be appreciated.

Thanks