Calling on 986 Forum Master Mechanics

[Jager]

Originally Posted by charles-007

I have Porsche Boxster 2.5 1998 and it has failed the emission test on to high Co. The car has been serviced including fuel filter, plugs, oil, air filter, oil filter and coil packs. In addition to this its had new Cats, new o2 senors and I have cleaned the Air flow mass sensor. There are no error codes coming up, have you any idea why the ecu is providing to much fuel so its pushing up the Co emissions? I have cleaned the air system and I have mixed the petrol with injector cleaner, could this cleaner affect the readings? Please can you help? I saw your post and have a similar problem but with the Co. In you search for you problem have you found anything similar to mine and if so can you help.
Thank you

I have never had an emissions level problem, just the CEL with P0430 code which seems to be a catalytic converter starting to fail. I have not come across a similar problem as yours, it might be a fuel injector issue or MAF sensor issue? Have you cleaned the Throttle Body? How is the idle and driving performance?