Surging on overrun and erratic Idle

[clarenceboddiger]

Has anyone had the problem of cutting out on tickover and a surging on the overrun between 2500 down to Idle speed.Have just changed the Idle speed controller but it aint cured it (although it is slightly better on tickover ) it still cuts out and runs really poor below 2200rpm.Could it be the throttle pot??? it does however run great once revs are up.Any help greatly appreciated as I've just bought the car and love it except for this problem.

[pies]

If you suspect the throttle pot see what it runs like unplugged if it runs better the TP is fubar

[harry1972m]

What Pies said and if not unplug the air flow meter and see if it is better - I had this a while ago it turned out to be both !!!!!

[MickS2]

pies said:

If you suspect the throttle pot see what it runs like unplugged if it runs better the TP is fubar

Is that always true? I thought that disconnecting the TP caused the ECU to go into LOS (get you home) mode and ignored all sensors. It may run better but this could be because another sensor, or dodgy wiring, was sending duff signals to the ECU.

Mick

[F908 Tim]

Worth checking your TP is not actually holding the butterflies in the throttle body open.
They do need to be fully closed before replacing or your tickover will have a mind of its own.
just a thought.

[clarenceboddiger]

Throttle pot was the problem ,tried the pot unplugged apparently it runs in a safe Mode and was smooth as a babies.Thanks for the responses