Idling problems and engine stall: one cause found

[Pisobiker]

Recently I sometimes had some very annoying engine stalling problems when stopping the car.
Tryed to clean up the ISV but this didn't seem to make a noticeable difference.
Checked the other transducers and connectors and everything seemed ok.
Also fuel consumption seemed to have raised a little. :mad:
Then a couple of days ago engine started to idle very roughly for only few moments while warming up. And this began to happen each time I started the engine.
Pulled out the water temp sensor and the intake air temp sensor and checked the resistance vs temperature: everything fine....

Changed the Lambda probe and all the problems were gone


Don't know if this thread has already been covered before (maybe in the old forum?), anyway I was just willing to share my engine simphtoms for anybody who may have the same problems.


Marco

[S2central.net]

Duff lambda probes are known for running problems alright - but I can't see the logic as to how it would affect idling after a cold start. AFAIK, the ECU ignores readings from the lambda at cold as they are inaccurate until the probe is properly heated for sufficient time.

Schtrange one ...


Paul

[Martynf]

I bet this question has been asked before... can the lambda be checked?

[Pisobiker]

Paul, I really don't know either !
I must admit the Lambda was one of the last thigs I would have checked (as in fact was ) .

Anyway changed the lambda => problems gone

Marco

[S2central.net]

Lambda can easily be checked -

1. Roughly with a multimeter (looking for lots of movement between 0.2 - 0.8V when idling or cruising)

2. More accurately with an oscilloscope

3. Can also be viewed and logged with VAG-COM (though it sucks as WOT because the ECU stops monitoring lambda)