E34 M50 hesitation on cold start

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

Reply to
Mike
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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)

Reply to
Dave Plowman (News)

I too have cold start probs on a '92 525, but hot or warm restart no problems - fuel pump?

Reply to
fishjam

Reply to
Mike

Don't forget to consider the ignition coils. They are 50 a piece for each valve and are one of the main ignition causes of immediate ignition problems.

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This will take some looking into by a mechanic. You want to isolate the problem before you throw money at it. Join this is you haven't already:

http://216.27.82.195/

Wait 5 days and get your membership card. Find a nearby BMW mechanic(not a stealership) that gives a 10-20% discount for the membership. Most do. Get your car diagnosed for those symptoms. Let them check the engine codes.

As it is now you are looking at 500 dollar parts no matter where you turn. Make sure you find the problem before the fix. Good luck.

ER

Reply to
Enoch Root

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