Rough running

[clarkey979]

Hi all,
I hope you can help, it's a difficult one with lots of potential solutions. My 997 had a misfire on starting on a cold damp morning, and is running a bit rough (apparently on both sides). The fuel has been checked (OK), spark plugs replaced and the coil packs checked (OK). Timing chains, upgraded bearing etc fitted and replaced in late 2015. Are there any other obvious areas that have been missed? Maybe somebody has had experience with this?
Thanks a lot
Ps - I joined in 2011, been a Porsche owner the whole time and this is my first post!!!

 

[C2dweller]

Sounds a lot like a dodgy variocam actuator - they seem to misbehave from cold and cause a few misfires. A code reader will point to the side at fault. You’ll see misfires across the whole of one of the banks of cylinders. There is one for the inlet and one for the exhaust. You are probably best replacing both for the respective bank, but if not try the exhaust one first.

Cheers Lee

 

[clarkey979]

Brilliant thank-you very much, great suggestion, we will have a look at this.