Fiesta idle problem

Don't remember your last post - have you checked out the Idle Control Valve - had exactly the same problems with my old Cavalier, and the wife had the same with a Ford Ka - both of which were proved by cleaning with carb-cleaner, but ultimately both cured by replacement.

By all means clear the ECU's adapted values by disconnecting the battery for

A faulty O2 sensor will *not* affect idle characteristics. It only has the ability to vary fuel trim by ~ +/- 10% at idle and cruise.

Tim..

If it's still "hunting" and you've replaced with a new (working) ICV, then it isn't that - and I don't believe removing power would help. If you still have the old one, try cleaning the ports with carb cleaner - search google for details and try refitting, just in case.

I still have the old one but the mating surface is badly pitted, which is why I replaced it. I might be able to skim it but I doubt it would be much of a job. Surely if the brand new one bought from Ford dealer has not made a differance then re-fitting the old one wouldn't either. Something I did notice at the weekend was a knocking noise which appeared to be coming from the air filter. I removed the duct from the air filter housing and found that the noise was coming from the throttle body housing end of the ducting. The noise was as if the engine was gasping for air yet the ducting was clear. Could the problem lie with the throttle body housing? What should I look for?

leaky inlet valve? just my pennies worth :)

After all this the car has been performing normally for the past couple of days! I am seriously considering buying an old car, and I mean an old one, before all these bloody sensors and ECR's.

Alex