fiesta courier diesel problem

It's getting too much fuel at low revs, so...a temperature sensor? I don't know a lot about the cold-start workings of diesels but it sounds reasonable to me.

Also, the electrical connectors on Fiesta sensors are prone to corrosion which is not obvious without seperating them, I've found, so it's worth seperating and cleaning every one you can find.

Si

What age is the van?

I'm guessing it's one off the newer ones with an EGR valve, as that's the symptoms they produce when faulty.

Standing at the front off the van with the bonnet up, on the right hand end off the inlet manifold, there is a large round valve, with a vacuum hose coming off it. That's the EGR valve. If you disconnect the small vacuum hose, blank the hose and take it for a run, the van should run far better. If this cures it, leaving it disconnected won't do any harm (well it may smoke slighlty more, and you might squeeze a couple extra HP out the engine) However it may be that the EGR valve has stuck open, in which case, if you take it off, it'll be quite obvious that it's stuck open. You can either fit a new one, or make up a blanking plate.

IF it's got the new TDCi engine then yes it's almost certainly the EGR. It's a common problem on the Focus diesels as well.

Modern ones are probably electrically operated - there doesn't appear to be a vacuum hose on mine.

This is the common fix for the Focus and works very well as you say.

I havent tried this on the Focus, but I am told that it doesnt work and the ECU flags a fault if the EGR valve is blanked with a solid plate, or the hose is dosconnected. -

There is no valve lift sensor on these and the ECU regulates the degree of EGR by looking at the MAF sensor reading dropping as it opens the EGR. Obviously if the EGR valve cannot pass any exhuast gas the MAF reading doesnt drop and the ECU knows something funny is going on.

There is no choice but to have a properly functioning EGR valve on the TDCi's.

Leaky PCV hoses cause it to throw a wobbly too.

Tim..

The van is R reg - 98 model. I have had a new EGR valve fitted a few weeks ago and this did not cure the problem

The van is R reg - 98 model. I have had a new EGR valve fitted a few weeks ago and this did not cure the problem

Have you tried disconnecting the vacuum pipe from the valve as I suggested before? It could be that the electrically operated vacuum valve is sticking, and disconnecting the hose from the EGR valve will prevent it from operating the EGR valve. It's the first thing I'd check before looking else where. It only takes a couple minutes to disconnect and blank off, and a short road test will show if it's worked or not. Also the EGR valve doesn't operate as much when the engine is cold, which is why it runs fine to start with.

There are a lot of Foci with a blanked EGR that have no problems, and no DTC codes appearing either.

Considering that many have been driving for over a year with a stuck valve because Ford couldn't make them work I'd say it doesn't upset them all that much.

I have disconnected the vacuum pipe and the difference is amazing - no black smoke and the van is well-responsive. To think that the garage mechanic was quoting over =A3500 to replace the fuel pump as a cure!!!. Thanks very much for the advice.

Obvisouly not! As i said I have had no direct experience of blanking the EGR on this engine, it was just what I was told at a Ford Technical seminar.

I'd be the first to try to blank off the EGR and if it threw up a DTC try to get around it. EGR is the work of the devil!!

Tim..