I have a 95 540i with about 190k on it. The car starts right up on
the first start of the day, and runs for about 5 minutes [if let alone
to idle, It will run longer if you rev the engine and keep doing so,
but stalls if left to idle.] After about five minutes, the idle would
go up and down then finally it would stall out. It would not start a
second time unless it is left sitting for a while [about an hour or
more].. I changed the crank and cam sensors, I swap out the idle
control valve, I swap out the MAF sensor, and the problem is still
there.. There's no check engine light. Any advice would be helpful.
Sounds like a fuel (or lack thereof) problem to me. Check for air locks
etc. in fuel lines and that the labyrinth into the tanks is not choked.
Next time is stalls try opening and reclosing the tank and then restarting.
(Long time Volvo owner)
I'm new to BMW's so could someone point out where the air locks are on
Fuel tank full? (Does it matter? It did on the Volvo when the in-tank
pump got weak.)
Do the in-tank pumps get tired or do they just die?
Anyone here old enough to remember Vapor lock? If this were an old
Chrysler,that's where I'd look.
Do BMW's vapor lock?
(Probably not related to the OP's question...)
My experience with (Volvo) fuel injection, as they get old the pumps
don't hold pressure.
Since the computer wants to see fuel pressure before it allows spark,
spinning the motor to start it doesn't work so well. Round and round it
goes but the computer didn't see pressure when the motor first turned,
so it's not sending spark.
But turn it over a second or two to build pressure, stop cranking then
turn the key again. Lites every time.
Don't know if this is a Volvo only FI quirk, or a FI quirk in general,
but I do know my '83 245 (300k+ miles) starts second click... every time.
Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here.
All logos and trade names are the property of their respective owners.