Idle is a bit lumpy on my 2.2 vectra C and have done all the usual throttle body clean, air filter ,plugs ,fuel filter etc and now thinking it's maybe the EGR valve sticking partially open and looking to purchase the EGR Cheater (sell them over on the Z22SE site), however I noticed that if I put the Air-Con On then the tickover is much smoother, what do you reckon is going on here guys, any ideas?
Cheers Pete