Fiesta idle problem

Hi all,

Had to slow down from 70 when the traffic on the motorway stopped, normally I can judge how hard to press the brakes to stop in the right place but this time I found I had to brake harder towards the end. When stopped I noticed that the engine was "idling" at 2k5 revs.

It went away after a few minutes and hasn't come back yet (this was Sunday). I've seen other Fiesta's idle fast when the battery is low but that's not it this time. No fault codes recorded by the ECU.

I'm thinking TPS atm but can't see how it would cause it; if the TPS incorrectly showed a slightly open throttle wouldn't it close the IAC and feed fuel, only to starve due to lack of air? Or does the IAC remain open unless it's overrunning?

Hmm.

Peter.

Reply to
Peter Spikings
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Or (he says, replying to his own post) presumably it could be something simpler like a sticky accelerator cable? :)

Thanks,

Peter.

Reply to
Peter Spikings

sounds like a sticking IACV but I also found this, which I had not heard before:

"This is a very simple fix that worked for me. My car is a 1995 fiesta 1.2 zetec. Try taking out fuse no. 32 (3 amp) and clean it. Worked a treat for me. Ive no idea what that fuse relates to in the engine, but was given the tip by a mate who is an RAC man. Was the first thing that came up on his laptop as a possible solution for this problem."

Reply to
Mrcheerful

I had this once. If it's the Zetec engine check the connection to the power steering pressure switch (low down on one of the pressure lines). On mine the wiring had been damaged (I guess by a stone or something) and it being open circuit fooled the ECU into thinking that it needed more revs ( to keep power steering pressure up).

The other thing to do is get the car rolling along in neutral above about 10mph and see if that pulls the revs up. If it does try declutching (as these cars have a switch on the clutch that pulls the revs down supposedly to make smoother gearchanges). If that does pull the revs down you'll know it's the ECU rather than a stuck cable.

You could also try an ECU reset to force the car to relearn its idle strategy. 30 mins of disconnected battery should reset the ECU but make sure you know the radio keycode first!

T> Hi all,

Reply to
Tony Brett

Useful discussion of this here

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Chris K

Reply to
CJK

Had exactly the same problem with my escort, turned out to be the TPS. If & when the fault comes back, try running the car with the TPS disconnected, if that's at fault the problem should go away, although you'll find you'll lack power.

Goodluck

Reply to
Dave Griffs

Ah yes - the fifth post there is exactly what I found with mine. Ford did a repair to the wiring loom and it's been fine ever since.

Tony

Reply to
Tony Brett

Hi all,

Sorry for the ridiculously late reply, I've just moved house and in the excitement forgot about this and I've still not got my broadband back yet (just returned to work today).

Thanks for all the help. The problem hasn't come back but I'll know what to check if it does (and I guess it will!).

Thanks again,

Peter.

Reply to
Peter Spikings

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