when my car is ticking over it is very spluttery, it sometimes drops the revs so low it nearly cuts out. i have replaced the lamba sensor thinking that might be the problem but it is still doing it.
Had the same problem with my 106 GTI. Try replacing the MAP (manifold absolute pressure) sensor as well, assuming the new lambda sensor was not damaged on installation???
Only other thing i can think of is to have a look at the idle speed stepper motor located in the throttle housing to see if that is dammaged or sticking??
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