Ford Focus (1998 - 2004) - 2004 1.8 TDCi 35-40 MPG on run?? Please help

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Thu 12 Mar 2009 22:10
2004 1.8 TDCi 35-40 MPG on run?? Please help - Knighty
Hi all, I've bought a Ford Focus sport 115 bhp 04 plate a few months back. Its now done 90k and since I bought it in December it has yet to impress me with fuel consumption. The car's had a full service, and has been driven easily with a mixture of town and motorway. Today I have done 430 miles on full tank 60 -70 mph all the way and it needs fuel again!! I think there might be a leak of sorts from underneath but only noticed wet patches underneath very occasionally.

What are the known faults with these engines? Is it likely to cost alot and worth getting rid of asap? My mechanic says he wouldn't know why MPG is so low (dont think his opinion is worth much based on this).

Any help would be appreciated, thanks.
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Fri 13 Mar 2009 08:54
2004 1.8 TDCi 35-40 MPG on run?? Please help - craig-pd130

If it's leaking diesel, you will smell it whenever you're near the car, I overfilled my Mondeo recently and it was VERY noticable outside the car ....

This is NOT a implied criticism, but how do you drive it?

If it's been driven gently most of its life the injectors may be a little blocked, etc. Before doing anything else, I'd suggest taking the car out, warming it up for 5 miles or so then working it hard on a motorway / dual carriageway for 30 minutes ... rev it up to 4,000 in 2nd, 3rd and 4th gear to blow the cobwebs away.

That can help. If it doesn't, then check the obvious stuff like the air filter -- has it been changed? Does the car roll freely in neutral, handbrake off (that is, are the brakes binding / rubbing a little?)

Have a look in the engine bay, especially around the intercooler / turbo etc. Are there any sticky, oily patches that would indicate a boost leak?
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Fri 13 Mar 2009 10:59
2004 1.8 TDCi 35-40 MPG on run?? Please help - Knighty
Craig, thanks for your reply.

Car does roll without power so pretty sure its not the brakes. It has been driven easily and has had a run on the motorway and around town a few times and has been driven at high revs a fair bit as I thought it might help.

Good point about the diesel - I have never smelt fuel around it (wasnt sure if diesel was so strong smelling). There's no sticky patches in the bay, and that car is totally mint which is why its so frustrating.

I've had the car serviced including air filter and fuel filter including the other stuff.

I may aswell run a gutsy petrol at this rate. I'm thinking of taking it to a diesel specialist.

Any other know faults with these engines?
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Fri 13 Mar 2009 14:02
2004 1.8 TDCi 35-40 MPG on run?? Please help - craig-pd130

You will certainly smell diesel near the car if it is leaking :)

Couple of other quick things to check ... try unplugging and re-plugging the MAF connector plug 5 times or so, the connector pins can get mucky & corroded, affecting the signal. This action 'wipes' them.

If you remove the engine cover, you will also see a plug connector on the high-pressure diesel rail. If you can get at it, unplug & replug a few times.

The only other thing I can think is the injectors are worn, but 90K / 5 years is a bit early for that.

Apart from that, maybe try filling with BP Ultimate / Shell V-Power, or adding an injector cleaner to the fuel and giving it another blast.
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Fri 13 Mar 2009 16:54
2004 1.8 TDCi 35-40 MPG on run?? Please help - quizman
I had a 52 reg 1.8 TDCI the same as yours. Mine was poor on fuel consumption, I had a chip upgrade at it's first service, it was a bit better after this but it had a job to get over 40mpg.
From what I've read on this site you can get good ones which are claimed to do 50mpg, but I often wonder how these figures are worked out.
I've got a Golf Mk5 1.9TDI now, it does 45-50MPG easily and is a much nicer car, but don't tell anyone or it will start the VW bashing again.
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Fri 13 Mar 2009 17:03
2004 1.8 TDCi 35-40 MPG on run?? Please help - injection doc
a work pal has a 1.8tdci & gets between 550-600 on a tank. Commutes 120 miles a day.
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