General engine reving

[grandad]

Hi i have a reoccuring problem,
It doesn't happen all the time but some times the engines revs or acelerates even when my foot is not on the pedal.The emgine then is going much faster then it should .i have taken it to many different garages but nobody has given me a good reason for this.

any ideas

 

[toad101]

ecu or temp sesnsor, the ecu could be thinking engine is cold and turnd on cold start system causing revs to rise

 

[rallycinq]

Check the rubber on the throttle cable is properly seated at the end of the outer cable.

Cheers

D

 

[cc1]

ecu or temp sesnsor, the ecu could be thinking engine is cold and turnd on cold start system causing revs to rise

From my experience, the engine revs increase when running lean. ie, when running out of fuel or an air leak at the intake manifold.

 

[fingers99]

As above. But see this thread too, after you've checked the rubber on the throttle cable. Since you seem to be getting a warning light, you might take the car to a Fiat dealer (or, at least. somewhere with a code reader) for a diagnostic.

 

[cc1]

Hi i have a reoccuring problem,
It doesn't happen all the time but some times the engines revs or acelerates even when my foot is not on the pedal.The emgine then is going much faster then it should .i have taken it to many different garages but nobody has given me a good reason for this.

any ideas

If it happens when you are decelerating, ie, when your foots been on the pedal, Then the throttle cable or throttle body butterfly may be sticking.
Also check the pedal moves freely and the cable is adjusted correctly at the throttle body. Make shure the cable routing is ok and it's not damaged (kinked).

 

[The Sultan]

mabey idle control valve they can rev the engine considerably when fully open

what cind of rpm is it doing on it's own

 

[frenchwood]

Possible causes:

Throttle Potentiometer Switch (TPS)
Sticking Throttle Cable
ECU fault
MAP Sensor fault
IAT (Inlet Air Temp) Sensor failing
Idle Stepper Motor Failure.

In a nutshell, check everything in and around the throttle body! First thing, take off the air inlet bx and hammer the inside of the TB with carb cleaner and leave it an hour then try again!!

Cheers