Aggressive Driving CEL - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Adam · 11-26-2009, 05:55 AM

Have the plugs been changed? The air pump being audible is normal. Did this just start or has it been going on awhile. Maybe just a tank of bad gas?

DamageINC123 · 11-26-2009, 06:37 AM

Thanks for responding. I am on 3rd tank since problem started. Plugs were replaced last year with 30,000 mile tune up by Porsche.
I am wondering if I have an intake leak. Maybe the computer is compensating for the leak until high RPMs are reached. Although it idles perfect and revs great.

Adam · 11-26-2009, 06:51 AM

Mmmm... I don't think it be an air leak on the intake side, because that would usually cause a hunting idle and roughness throughout the powerband like you thought but it wouldn't hurt to have a vacuum leak test done. Maybe have the coil packs inspected on banks 1 & 3 and while you're in there inspect the plugs and see how they look.

DamageINC123 · 11-26-2009, 06:55 AM

The techs had mentioned doing that but after the MAS was cleaned the problem temporarily went away and the coil packs were never checked. I will check them out.
I do have aslight vibration at high RPMS. Its only noticed with the top up. The techs that test drove it did not mention the vibration. However its responsive under throttle and and idle is perfect.

Lets say I do have an intake leak. Do you know about what the cost would be to correct?