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Old April 24th 06, 09:38 AM posted to alt.autos.bmw
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Default E34 M50 hesitation on cold start

In article >,
Mike > wrote:
> my '92 525i hesitates on cold start. however, car starts right up with no
> hesitation if i turn key to on pos a couple times before actually turning
> over starter. fuel pump? BTW, car only has 42,000 miles. i recently
> purchased from original owner and brought service up to date....cooling
> system and transmission service. thanks for you input. Mike


I *think* the fuel pump runs for a short burst when you switch on to fully
pressurise the system then stops if you don't immediately start the car.
Then runs again when you operate the starter, of course, and continues to
run after that. Sounds like you have a leak somewhere or a faulty non
return valve in the pump. Even leaking injectors. A pressure check of the
fuel rail should show this - it should retain full pressure for some time
when the engine is switched off.

(If you had leaking injector(s) I'd expect at least slight problems on a
hot restart after say a couple of minutes)

--
*Keep honking...I'm reloading.

Dave Plowman London SW
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