ABCar

Hello, I am a new 964 owner. My car has an idle surge issue. Most notably it occurs after the car is warm. It also has a very rich exhaust odor after the car is at operating temp.
Car is modified with lightened flywheel.
On letting out clutch in first gear from stop the engine seems very confused and surges and drops to the point of stalling or racing at this transition.

I have heard that a light flywheel can cause the problem because the idle positioner cannot act fast enough to work with it. Any help and feedback welcomed. And thanks.

Kappi2907

O2 sensor issue.

ThomasC2

I had a similar problem, see my recent thread "Bad idle - solved". Hooked up the diagnose tool and got an error code for the "O2 sensor". I first checked the connector in the engine bay and discovered that the connectors weren't fully connected. Pushed them together and problem was solved. Next step is to replace the sensor, do you know if it’s old or replaced some time? The easiest way to trouble shoot is always to start with the diagnosis tool (Every OPC has them, and many other workshops) and look for error codes instead of starting to replace stuff.

ABCar

Thank you, will get the diagnostic tool for sure.