I used to get that on my A8 3.7 when I first got it.
Only did it if I went straight into reverse after starting. if I went to drive first and then back to reverse it was fine.
I had to replace the vacuum hoses for the secondary air injection which were missing and also fitted a new MAF. never did it again after that
__________________
2002 3.7 quattro sport (SOLD)
|