Ford Mondeo 1.8 diesel engine hunting

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Thu 21 Oct 2004 14:21
Ford Mondeo 1.8 diesel engine hunting - Shotgun
Hi,

My Diesel Mondeo (1998, 96,864 miles, regularly serviced, no previous history)has recently got sick. It now requires extra cranking to start whereas it used to start virtually as soon as the glow plug light went out. When the vehicle is at normal operating temperature the engine seems to hunt. This is noticeable at low rpm. At a steady 1500 rpm with the vehicle stationery and out of gear the rpm will randomly drop to 1250 and then back up to 1800 before going back to 1500. When driving at around this rpm you can feel the engine hunt when you apply a throttle change either upwards or downwards in speed. There is no obvious evidence of any smoke from the exhaust. The problem does not appear to be there at high rpm but this could be the higher frequncy masking the hunting effect. Can you offer any advice.

Many thanks

Chris
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Thu 21 Oct 2004 15:49
Ford Mondeo 1.8 diesel engine hunting - RichardW
Chris,

Sounds like it's got an air leak on the fuel system. Try pumping the hand primer (if it's got one) before cranking the engine. If it now comes straight to life, proof of an air leak - all you've got to do is find it! favourites are the injector leak off pipes, fuel filter housing, hoses in the engine bay. Can be a trial to find....


--
RichardW

Is it illogical? It must be Citroen....
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Mon 25 Oct 2004 12:01
Ford Mondeo 1.8 diesel engine hunting - Shotgun
Hi Guys,

Further investigation at the weekend reveals the following:

The boost diaphragm is not split.

The idle solenoid is working.

The busbar and heaters are ok.

It idles ok.

It seems to run at high speed ok.

It missfires at around 1500 rpm and puts out white smoke with a hint of blue during the misfire. It feels as though the engine is about to stall occasionally when this happens. I have noticed that the anti-stall actuator seems to be working a lot, even when the misfire isnt happening and I am just moving the throttle lever.

I suspect the problem may be air in the system. I had the filter housing replaced about 18 months ago by Ford.

Any further suggestions?

Regards Chris
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