'97 Fiesta 1.25 Zetec woes

Replace the coolant temp sensor (CTS) its also in limp home mode (LOS - limited operation strategy).

The inadequate fuelling when cold and 4000rpm rev limit are signs of failed CTS and LOS in place.

Tim..

Thanks Tim, I'll do that tomorrow.

Just read the BOL and it says LOS will continue until the fault code is erased. Rats, looks like I'll have to get the scanner anyway.

Anybody know if the fault code can be erased without a scanner? I've heard that disconnecting the battery for half an hour or so will clear some stuff from the ECU. Will that clear the code?

Cheers

Again a symptom of the ECU being in LOS mode.

They are prone to this even when operating properly- fix the underlying fault first and this will probably go away.

Depending on which vacuum pipe you are looking at, it will be either for the charcoal canister, or more likely the heater recirc flap.

The air

They are PTFE coated to resist oil and carbon deposits. If it is fairly clean with no ring of carbon behind the throttle plate, just use a dry cloth to clean it. Carb cleaner will strip the ptfe from it. Brake cleaner or meths is less aggressive and can be used gently.

They can be, and only 5w-30 should be used. If it was suffering from valve stick from the wrong oil you would have a very poor cold idle, prone to stalling with misfiring, and difficulty in restarting whilst cold.

Being a 96 car i expect you have neither the IV nor the V, but what is know as the FOL ecu, which was an intermediatory variant. Treat it as an EEC IV, but use an FCR on the 16pin connector.

Tim..

Yes. NB radio code.

Allow the ECU to relearn idle strategy properly when you re connect. The handbook gives details i think.

(start from cold with no throttle, allow to warm fully at idle to a couple of fan cycles, then drive for at least 3 varied miles.)

Tim..

Yes. Although a couple of minutes should be long enough. Mike.

Thanks Tim.

Cheers Mike.

The pipe is connected to a solenoid on the bulkhead near the brake servo. Now you say, I'm sure it's the canister pipe. The wire colours on the solenoid suggest that too.

That's reassuring, thanks. The oil looks quite clean, perhaps it's 'next weekend' not 'tomorrow' urgent now!

Cool, thanks. Presumably it won't give much more than basic fault codes then? Do you know if I can get flash codes from it, like the 3 pin connector of the IV?

Thanks very much for your help, Tim. I was hoping an expert would answer

- they clearly have!

I'll let you know how it turns out and buy you a virtual beer.

Cheers John

You can try, but as I remmeber it was abit of a hybrid, and although the 3 pin connector was present, it wouldnt work...

Tim..

It's all fixed and working nicely.

It was the coolant temperature sensor. 'We sell a lot of those' said the spares chap...

Haynes BOL says to drain the coolant, but a plastic bag over the neck of the expansion tank with the cap screwed back on stops much escaping.

I measured the resistance of the new one, it was 27K ohms. Just to prove the point I measured the old one once it was out. I was gutted to find it read the same. Carried on anyhow and measured it a while later, this time it was 40K, so it was an intermittent fault.

Many thanks and much kudos to Tim, who diagnosed it in one. I owe you a beer sometime!

Cheers John