A6 2.8 started popping and I think it maybe the vacumm system.Back firing through the exhaste comes on even more when the A/C is on. I have changed out some of the vacumm lines. Can a purge valve be cleaned and reused. Just was wondering.

 

Timing

Try pulling codes and checking the cam position sensors and timing belt.

See if you have a P0300-6 the last number is the cyl maybe you have a messed up coil or ICU.

 

Well it's not the coil pack, also cleaned the purge valve and replaced all the vacumm lines. I will keep lookin or it's off to a good shop.

 

If its popping out the exhaust its not "backfiring" Its got more of a hicupp, too much or not enough fuel. DO you have a vag com? What does the long term fuel trim say in data block 32?

 

Don't have a Vagcom yet (so if there is anyone around Houston that has one there's a cold beer in it fir them). I did stop at Auto Zone and the P0301 code came up. Missfire on #1 cyl. Going home to read the spark plug to see just how they look. Check out the plug wire and all this. More later.Thanks for the help...