911 idle?
 

Wondering if anyone knows what would cause my86 911 at start up to idle fine for a few moments then drop to almost a stall then idle back up to normal idle, sometimes it will go all the way and stall. It gets better when hot but still hesitate and sometimes, stall when hot. When accelerating seems to be fine, it only seems to do this between idle and 2000 rpm.

Provide more info. Is everything stock and have you done anything to
the engine, e.g. mods?

Engine is all stock 3.2

Could be a vacuum leak. Check the hose connections and make sure the manifold nuts are tight.

You have to start checking the basics:

1. temp sensor
2. fuel pressure
3. idle valve
4. idle switch
5. battery voltage when problem occurs (overcharging alternator)

Check out this web site (www.systemsc.com) on the Diagnostics page
under Poor Running.

Scootr:

I had very similar symptoms in my 84. I replaced the head temp sensor, the idle control valve, and the O2 sensor, but nothing helped. Then someone suggested that I have the mixture adjusted. I took the car to my pals at TRE and, BINGO, problem solved.

Try having the mixture checked before sinking a bunch of bucks into parts. Sometimes the simplest solutions are the best ones!

Good luck.

Does it seem to be running rich by any detectable tailpipe odor?

there is no dark smoke under acceleration, or does not seem to smell like it is running to rich.

You might do a search on intake manifold vacuum leaks.

Sounds like you want some more "darts thrown" at the problem versus
doing a little troubleshooting yourself. People have provided ideas, have
you checked them out?

or maybe the problem is fixed and he's just out having fun! ;-)

I'm sure we'll hear about it one way or the other.

No I just havent had time to check-it-out but as soon as I get a chance I am going to get busy, I really do appreciate all the information, Keep it comming.