14 replies to this topic

[Mistry]

Hi, this is my first post here and im hoping someone here can help me. I drive a Fiesta Mk4 1.25 Zetec LX 1999.

When I drive off in my car without warming up the engine it tends to stall a couple of times at junctions and roundabouts as I slow down towards them. The revs seem to drop when I engage the clutch and sometimes drop extremely low at which point the battery light flashes as it struggles to keep it at the correct idle. If it drops too low the oil light comes on too indicated the car has stalled.

The weird thing is when my engine is warmed up, the car drives perfectly.

Ive been told it is the "Idle Speed Control Valve", and I have cleaned it out with carb cleaner and WD40 with no change. I recently bought a replacement OEM idle valve off ebay but when I installed it, the car idles at about 3500 - 4000 rpm!!!!!

Just as a note, when I start the car without an idle control valve, the car also idles at about 3500 - 4000rpm! Is this suppose to happen?

I put my old valve back in for now but I'm not sure what to do. I hear the Ford dealers charge £100 or so for a new valve!

Sorry for the long post, but I've given all the info I can hoping someone may come to a conclusion from this...it's driving me NUTS!

[vinnyvangough]

Hi and welcome to the club.

Sounds like the idle control valve and i know there are different ones so it may be that the one you bought off ebay is not the right one.

[Mistry]

Hi and welcome to the club.

Sounds like the idle control valve and i know there are different ones so it may be that the one you bought off ebay is not the right one.

Hmm...but do you have any ideas about why my car revs soo high when I start it without an idle air control valve in at all? I have heard others say that their cars rev at bout 1500 - 2500 rpm when no valve is connected?

[Rikos]

Not sure why it goes to 3500-4000 revs but definately sounds like you have bought a dodgy one of ebay.

O and welcome to the club.

[Mistry]

Not sure why it goes to 3500-4000 revs but definately sounds like you have bought a dodgy one of ebay.

O and welcome to the club.

Hi, well I will try and get a replacement or get a genuine Ford one if I can and post results up.

[Rikos]

Sounds like a good idea, hopefully this will resolve the issue.

[mintalkin]

could also be tps (throttle position sensor)

[Mistry]

could also be tps (throttle position sensor)

I don't know how the parts work but would the TPS not cause a problem regardless of whether the engine was hot or cold?

[mintalkin]

overeving is sometimes connected to the tps voltage wrong

[Mistry]

Ok, I just got back from the dealer with a genuine Ford IAC valve and fitted it in the car. While the engine was still cold I took it for a spin and it happened AGAIN!!!!!!

Should I reset the ECU after changing the part? Or just take it as the IAC is NOT the problem?

I don't know what else to do now! Why is this only happening when the engine is cold?

[mintalkin]

could be a temp sensor sending the wrong temp to the ecu

[Rikos]

Did you ask ford what they thought the problem may be?

[Mistry]

Did you ask ford what they thought the problem may be?

Yeah I did, but the guy said he can't say without doing a diagnostic. I've heard a lot about people with a similar problem who have had a diagnostic done and returned no errors. If the problem continues I may have no choice but to do so.

[Mistry]

Following the dropping revs my car began to vibrate at low revs quite violently and wouldn't pick up from zero without what felt like a continuous misfire.

I changed the spark plugs but that did not help the problem.

Took the car for a diagnostic and was told I needed a new IGNITION COIL & HT LEADS. This solved the misfiring problem, but the drop in revs triggering the occasional cutting out and battery light flashing problem as mentioned in the first post is still present.

[Mistry]

Anybody here having the same problem? It's beginning to irritate me a lot because aside from this, the car is pretty much perfect.

Just out of curiosity could sticking valves in the engine cause this sort of thing to happen when the engine is cold?

If so what's the best way to cure that?