First off I realize diagnosing & troubleshooting over a forum isn't exactly easy or effective, but I'd like to be armed with as much information as possible before I take it in and there are some intelligent people on here.

I have a 2007 997.1TT that is throwing some codes.

Codes:
P2189 - System too lean at idle bank 2
P2187 - System too lean at idle bank 1
P0507 - Idle air control system rpm higher than expected.

Behavior:

I noticed a few months back that occasionally while coming to a set of lights, clutch in and the revs would rise 500rpm or so then gradually come down. Sometimes they would hang at 1200rpm is then come down after a few seconds.

No codes at this point.

Then I through the codes and while I'm seeing the same behavior, it has rev'd higher than it was previously. It also hangs and takes longer to let the revs come down. It also isn't idling too well. Idle will dip, it catches it and they return to normal. Rinse and repeat. There is a repeatable pattern to the idle seeking.

It is going in next week but I if anyone has some ideas for things I can check myself that would be great. Too me (and my amateur backyard knowledge) it feels like a vac or intake leak. The plumbing on this car is so difficult to access though I really can't find anything obvious from the little I've poked around.

Welcome any feedback.

Cheers

 

I'm going to guess and say the maf sensors might be partly responsible but it's odd that both sides at once.


I've been going through some idle issues lately too, but they sound a little different than yours. I had thrown a code p0011 and long story short I had my camshaft actuator changed. Prior to this you could tell something was wrong and also on the datalog you could see some "issues" with the timing. That's been sorted out but the idle issues are still there to a certain extent. Sometimes when I come to a stop the revs drop to about 500rpm and then bounce back up. Occasionally they don't bounce up and the car stalls. PTF sent me a slightly modified tune and it now only occasionally occurs when the a/c is on (higher load on the car I guess).


Anyway, my plan was to change the O2 sensors next spring as well as the plugs and coils. Dzenno at PTF had wondered about the sensors when the car was on the dyno, as well as the plugs not quite cutting it for my turbos and tune.


good luck with it, and do post any followup.