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View Full Version : 2001 2.0 ALT runs/sounds strange on cold starting



bagpipingandy
18-06-2014, 12:46 PM
Hi, had this issue for a while now

on cold start only, the 2001 A4 2.0 petrol ALT engine, starts ok but a strange noise is heard for 3-4 seconds at tickover, almost ticky/bad mixture sound, and then goes to normal tickover and then all ok, only happens on cold start, fine starting after that.

To me it sounds & feels like a motorised or vaccum flap sticks open (or closed) longer than it should and takes this few seconds to sort itself, changing the tone of the intake anf running of the car, It doesnt so much run faster just sounds like not getting the air or mixture correct for the 1st few seconds at cold start.

no fault codes stored,

I recently renewed large intake hose and then vaccum hose set up to see if it cured it but its still the same, on cold start only, all other times starts & runs fine

is their any flaps used for cold starting on the ALT I could investigate? or other reasons welcomed

regards

Andy