martymiami

Hi all, new on here, I also post regularly on the other Porsche forum, but I thought I'd see what people here had to say as well.

I have an 86 Carrera 3.2, around 86k miles.

I have some ongoing idle issues. Base idle (jumpered with SW chip) is set to 880 - but when I remove jumper after setting base idle, idle drops to 780.

Also, when cold, car starts and idles fine, but after pulling away for the first time, and for a few minutes after start, every time I clutch in, the idle drops to 200 (or in fact stalls) before recovering.

Once car is warm, all good. This is the list of stuff I've done recently:

• New copper plugs, cap and rotor (better start and idle)
• New Steve Wong chip
• New DME relay
• New Cylinder Head Temp Sensor
• Checked for vacuum leaks (none found)
• Checked idle switch - seems to be clicking fine
• Checked air fuel mix - running rich right at start (13) - then leans out to between 15.2 to 16 at idle (reading from tailpipe so should show a bit lean at idle - then AFM between 14.4 to 15.2 at load
• I also did try to adjust the idle mix in the AFM (I feel like the idle is slightly lean), but the screw was almost all the way tight, which i think is to the richest setting, so I left well enough alone. Not sure why it's set where it is or if that's correct or compensating for something.

Next on the docket is pulling the Idle Control Valve, and checking AFM...any other ideas?

lightemup67

I'd start with the AFM. Your symptoms sound similar to what mine was doing. I took apart the AFM, cleaned and oiled the track inside, and its running much better.

After that Idle Control Valve and O2 sensor?

Good luck.

martymiami

Thanks for the response. Something is funky about the idle, so I think you're right, it has to be one of those things. I did test the O2 sensor and it seems to be OK, but since I already did the CHT, I may as well.

Removing and cleaning the ICV seems easy, the AFM? I'm not sure. I can tackle both this weekend. Bentley Manual arrives Friday.

lightemup67

AFM is super easy. Its really just removing the Air filter housing, removing the AFM, removing the cover, and cleaning it out. Removing the cover was a little hard, but it just took patience.

There are lots of treads and youtube videos to look at. Good luck!