BMW 740 rough when cold

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Tue 6 Mar 2007 15:30
BMW 740 rough when cold - MCH
My mates 1994 BMW 740 is running poorly when cold. It starts fine and feels as though the mixture is OK for the first few hundred yards.

After that the revs drop considerably and it feels as if it is going to stall, but doesnt. When fully warmed-up it runs sweet.
Its as if the sensors think the engine is warmer than it actually is. Although the car has done 140k, the engine block has only 45k (BMW replacement).

The plugs are new and it has been recently serviced at an independent (the problem stems from before the service). The car does mixed mileage with occasional 500 mile round trips. Mate hasnt a lot of car DIY experience, but could anyone point him in a likely direction or does he re-mortgage and take a trip to main dealer diagnostics?
Thanks for any ideas.
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Tue 6 Mar 2007 15:40
BMW 740 rough when cold - madf
Sell it when running warm... money pit.
madf
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Tue 6 Mar 2007 15:40
BMW 740 rough when cold - Pugugly {P}
What part of the Country ? Plenty of BMW specialists out there who'll do the job far cheaper than the "nice man in the tie" can.
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Tue 6 Mar 2007 15:52
BMW 740 rough when cold - chukter

>>>>>What part of the Country ? Plenty of BMW specialists out there who'll do the job far cheaper than the "nice man in the tie" can. >>>>>


www.unixnerd.demon.co.uk/garages.html
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