Ive got the 2 litre blacktop engine in the mk4 fiesta with out power steering.Im using the mondeo 2 litre ecu and wiring.When the car idles on choke its ok and when the car warms up the choke comes off a bit but not fully.Ive disconnected the idle speed control valve and it cut out so its doing its job.I read that when the mondeo,focus had power steering it had a power steering sensor so when the car was under load and you was turning the steering wheel the car wouldn't cut out and idle a little higher to compensate.Im left with just the multi plug now and I think the ecu thinks the power steering is there hence the car reving a little higher than normal.is there anything I can do to loop the plug out completely?And do the throttle bodys ever clog up on these engines?Im using the black 2 litre throttle body on the plastic inlet.

 

The car still over revs even when I dip the clutch.Tonight it cut out twice on the way home from work

 

I also unplugged the throttle postion sensor and nothing happened the engine just continued running

 

MAF? Or air leak in vac pipe to servo?

 

Ive tried the maf if left unplugged it wont start and it will cut out if running.Ive scanned the ecu and im getting no fault codes

 

I played around with the servo hose just now the bit that connects to the servo its self.It wasn't sat flush so I have corrected it and it is a little better but its still not 100%

 

It would be the opposite effect, i.e. the pressure switch alters the voltage.

I should not have any effect with it being open circuit.

There is no choke, the ISCV determines the idle speed, I should think if you had an air/vacuum leak you would notice it running badly. Sounds like the valve is open to far.

Martin

 

Hi Martin thanks for your input.Ive ordered a new tps sensor so I should have that this week.I will go scrap yard at week end and pick up another iscv and give it a wirl

 

I doubt it's the valve itself, rather it is being told to ac like it is.

A bad TPS calibration can cause these sort of issues, but then that would cause problem when driving it.

Martin

 

So you reckon a bad tps would be the problem lol.Its hard to pin point the problem.Im not gonna no till week end anyway.My new tps sensor has arrived now

 

I think ive stumbled across the fault now.When the car is warmed up and I unplug the iscv the revs cut to how it should be and idles fine.But if the car was cold and you tried starting the car the engine would cut out