[Redman]

Anybody came across this issue.

I recently changed the head gasket on an astra g x20xev, had the head skimmed, re assembled with complete sensor change, new idle stepper motor and throttle position sensor, no ebay crap ether all Lucas/GM/Delphi, timing is spot on, changed the cam sensor wiring, engine starts and runs, but like like a bag of shit, won't rev clean, and doesn't pull when driven. I've also replaced all the vaccum pipes and it's had new plugs. Plugged my laptop in and ran Delphi dianostic, and it indicated a p0340 cam circuit signal error, no EML light though, cleared the code., didn't reacure, but issue still persists

Has anybody come across this before?, it's doing my nut in!

 

[ayresyy]

It could be related to the cam sensor, if you still have the old one then its worth just swapping it back for a test. The other suspect to check would be the MAF. Was it genuine Siemens/Bosch one you fitted?

 

[Redman]

Yeah, is an original GM sensor (old new stock), the MAF is a Bosch which is less than 3 months old, tried the old units, still the bloody same!

 

[ayresyy]

Does it run any differently with the MAF unplugged?

 

[Redman]

Does it run any differently with the MAF unplugged?

Yeah tried that, EML comes on and idle oscillates and doesn't hold steady, whck kinda ndicates the MAF is doing its job, plus on Delphi diags I can see the voltage value of the sensor increase under increased revs

 

[ayresyy]

Only other things I can think of is the TPS that you changed, and maybe the O2 sensor, but the 02 sensor shouldn't effect running during WOT.

Did you carry out a compression test since rebuilding the engine?

 

[Redman]

Yes, thought about about compression, tested it, all good at 187-190 psi, Tps is okay, I can see the voltage increase on Delphi diags when revving plus I can hear it operate when tested on the same