Engine stalling problem

[msrc2]

2000 996:

HELP! I have a 2000 996 that hasn't been behaving well lately.... The sequence goes like this: engine starts (always, hot or cold). Idle surges constantly. When underway, engine runs fine (warm or cold). At my first red light the engine stalls as soon as I put in the clutch. Restart engine (easily). Drive some more...until next red/stop sign. ..Engine dies again. Drive and repeat, drive and repeat....etc.

This engine will die as soon as I put in the clutch when approaching a full stop...HELP PLEASE. IDEAS???? (hasn't been to dealer yet)

Thanks! msr

Edited December 16, 2004 by msrc2

[Loren]

Some thoughts...

Same tank of gas? How many miles on the car?

When was the fuel filter changed last?

Have you cleaned the throttle body (inside) with carb cleaner?

[msrc2]

Loren,

22500 miles

I have been through several fresh tanks of gas.

Fuel filter changed @ 20,000.

Haven't touched the throttle body.

Note: The car runs extremely well under power, like on the freeway or surface streets.

[Loren]

Well, if it were mine I would take off the air cleaner from the throttle body and see if there is black carbon build up. If so, I would use some carb cleaner on the inside of the throttle body until it is clean. Since your car is egas you will need to move the butterfly with your finger to get inside the throttle body. It's okay to use a rag as long as it is lint and deposit free.

[1999Porsche911]

If you simply slip the tranny into neutral when approaching a stop WITHOUT TOUCHING THE CLUTCH, will the car stall? Is the stall happening when applying the brake at idle? Thinking vacuum leak here.

[djantlive]

1. Any engine error code?

2. Possible vac leak somewhere bc you are stalling and idle is irratic. Spray carb cleaner generously around possible areas. If idle surges when you spray, that's where the leak is.

3. Possible transmission synchro/computer issue. Unlikely since your idle is also irratic.

#2 will be hard to diagnose. I'd suggest you have a Porsche dealer or specialist find the leak bc they'll know where to look. You can look at vac hoses for leakage and possible manifold/pipe gasket leak.

[msrc2]

PROBLEM RESOLVED !!

First, THANKS to everyone that offered their insights as to this stalling problem. Loren, you nailed this one.... Once the throttle body and everything was cleaned up, it ran great! Smooth idle and NO more dieing at red lights!

Thanks again guys! msrc2

[Loren]

Glad it's taken care of.

I use a bottle of Cheveron Techron (in the gas) about every 3000 miles to keep things clean.

[SlvrSurfer]

Hello,

I have a MY99 996 with 70K miles on the clock with terrrible idle. Just curious on how you cleaned the throttle body out. Please elaborate if you can put in a step-by step process I can fully understand how to DIY. I know it has been discussed here and there but I just need someone to break it down for me.

Thanks

ED