[quest63]

recently did some work to my car and now have the above running issue which may or may not be caused by the work done.

I did rust treatment and painting under both front arches, fitted a new radiator cradle, fitted new horns fitted smoked repeaters and contoured mudflaps.

While doing the passenger side I noticed the locating peg that locates the bottom of the airbox to a bracket on the body was not seated properly so I pulled it down and back about a half inch or so into the correct position.

Now when I dip the clutch to slow to a stop the revs rise quickly and sharply to 1500 rpm only coming down to normal idle when I have braked to a stop. I can slow down and brake to almost a stall without using the clutch so the revs arent stuck at 1500 so to speak, but as soon as I dip the clutch the revs shoot up to 1500 rpm

Dipping the clutch when in neutral and stopped does not cause it to happen. I checked the clutch pedal switch was in position. it is.And I did an ECU reset which did not solve the problem.I also checked the power steering pressure / flow switch was connected, but my understanding is that like the clutch peadal switch its likely to cause stalling not increased revs.

Help please its driving me nuts

[StevenRaith]

My car does this, I assume it is a case of They All Do That Sir. Most noticable coming up to junctions and traffic lights.

Be interesting to see if anyone thinks this is odd.

[d170sam]

Mine did this too, I replaced the tps which made no difference, also cleaned the maf and idle speed control valve, which again made no difference, in the end I found it was the valve that allows air from the fuel tank in to the inlet system, the valve is on the soft back board in the engine bay in-between the connectors for the lambda and the main fuse box it's got a connector in top and a 6mm ish push on hose connector either side, I got a new one from ford and did a ecu reset and now it's cured

[d170sam]

Mine did this too, I replaced the tps which made no difference, also cleaned the maf and idle speed control valve, which again made no difference, in the end I found it was the valve that allows air from the fuel tank in to the inlet system, the valve is on the soft back board in the engine bay in-between the connectors for the lambda and the main fuse box it's got a connector in top and a 6mm ish push on hose connector either side, I got a new one from ford and did a ecu reset and now it's cured

[quest63]

Could I see a piccie of this please

Thanks

[StevenRaith]

quest63, on 31 December 2011 - 03:20 PM, said:

Could I see a piccie of this please

Thanks

+1

[d170sam]

i dont have a pic, sorry, there might be one in the gallery

[quest63]

Thanks I found it

[volcomstone411]

that's the purge valve. It realeases added pressure from the tank but it might be leaking fumes back into the inlet causing riding of the revs. What you can do is disconnect the vacuum pipe and then plug inlet with a finger and see if it does it then. Seems strange tbh. There is a switch on the clutch pedal itself. But i assume that is working as the clutch is being depressed. But worth a change. think they are like a £6 from ford

[quest63]

An update on the problem is that for whatever reason the throttle is sticking and is taking a few seconds to come down to idle.I dont usually blip the throttle when stopped so didnt notice this,When stopped if I rev the car
it sticks at 1250 rpm not the 1500rpm it rises to when I dip the clutch when slowing to a stop when driving, then settles down to normal idle. I'm guessing the clutch switch is just confusing the ECU to the tune of another 250 rpm.

Idle control valve is currently off the car and has just been cleaned and will be tested tommorow.

Will report back then

Quote

What you can do is disconnect the vacuum pipe and then plug inlet with a finger and see if it does it then.

Will check this if necessary thank you

This post has been edited by quest63: 03 January 2012 - 06:01 PM

[volcomstone411]

may also be the throttle position sensor...they are cheap and dont last long

[quest63]

Quote

may also be the throttle position sensor...they are cheap and dont last long

Yep I have that down as a possibility but should cleaning the icv not sort out the problem and blocking th inlet vacum pipe not work I would then still be stuck wondering if the electrical part of the ICV has failed
or if the TPS has failed. Neither are that expensive but I definately need better odds than 50 / 50.

[volcomstone411]

well tps tire anyway. so it's never a loss to replace them. On a competition car, it's good practice to repalce them every outing anyway. They are so unreliable. That's why manafacturers are trying their best to make a reliable brushless one.

[MattC]

I had the same problem in the FRP- it turned out to be the start of a sticking accelerator cable.- It eventually stuck at 4,000 rpm whilst doing 70 (+) in morning traffic on the M25...

[quest63]

Although I had checked it earler and discounted it as the cause of the problem it turned out to be a broken wire to the power steering flow / pressure sensor
which is a known cause of idle problems. I have bodged it up temporarily till I get a new connector and its cured it a treat.

Thanks for all the help