Good day all,


I have a 2002 996tt (non X50) and recently had a Kline (cat delete) exhaust installed. As of recently, as its been getting colder, my car has been idling higher. About 1k to 1050 rpm. The high idle doesn't happen all the time. The other day it started idling high at a stop light and of course my car threw a CEL P0570 for high idle. I also found CEL code P0420 for my cat delete. The car never threw a CEL for the cat delete, it seemed to have just stored the code.


I bought the car from a Porsche dealership and the car had some aftermarket enhancements on it. I dismissed a tune due to the car hitting no more than 0.8 bar. But now I'm wondering if the car in fact has a tune due to the non-cat CEL never popping up. Everything I've read about tunes suggest that I should be getting at least 1.0 bar with a tune. So, with all this said, could I more than likely have a tune on the car and maybe I have a vacuum / boost leak that is contributing to the high idle and possibly not allowing for full boost psi? Hopefully I explained this correctly so it makes sense where my head is at with this.


I very much appreciate any thoughts on this!!

 

Have you ever done a boost leak test?
Do you have a durametric cable to do some logging?
And did the exhaust come with any sort of mini-cats or O2 extenders for the secondary O2s?

 

I have a Bosch OBD2 reader. I have spacers where the cats would normally go.

 

Sorry, no boost leak test done before.

 

Sounds like there is a vacuum leak. To get more pronounced different conditions. Feel free to call me if I can help

 

I mean do the secondary O2's screw in directly into the exhaust or is there some sort of extender or something between the O2s and the Bung?

 

Oh Gotcha. From what I know of it, the O2s are screwed into the exhaust.

 

Thank you Sam! I called my indy and he agrees with it being a vacuum leak. Getting it tested Monday. Loving the exhaust man! Thanks again!

 

How do you know you had a tune? .8 bar is stock for non X50 car. Maybe someone just popped in there and disable the CEL light??

 

Yeah, that's a good point. I don't know that it had a tune, just speculation. Wasn't sure if the CEL could just be disabled.