I have recently come across a strange problem. Only occurs after car has been turned off and sitting for 1-2 hours. Weather not affecting and sitting overnight, car starts normal and nice.
After the 1-2 hours of sitting, engine will turn over not the 2 or 3 usual times for ignition, but needing 10-12 times to finally start. Then it starts very poorly by making a sputtering sound and only idling at 200-500 rpms, instead of the usual instant 1000 rpms. This is very annoying and a few times the engine has turned over 10-12 times and didn’t start at all. When a person starts the car up every 1 to 2 hours, say on a busy errand weekend, it pretty much ocurrs each time. When my wife uses the car just in the morning for work and at the end of the work day, it is not noticed for some reason…
Please help!
Squirt some starter fluid in the intake when it won’t start and see if it starts. That would let you know whether it’s the fuel pump or the ignition. If it does not start then it maybe the cam sensor. They don’t like heat. You could crack the the hood and see if that helps.
My best guess would be a temperature sensor that is telling the car that it is colder than it really is, and is causing flooding. Problem is, that this car has several temperature sensors, so figuring out which one is inaccurate may be a challenge. My first suspect would be the water temperature sensor that talks to the fuel injection circuit. This is not the one in the lower radiator hose, that one turns on the electric fan. The suspect sensor is probably on the driver side of the head and is really tough to get at, because life is like that.
Thanks guys. I will post on a Bimmer forum as well. I will pass this information to my local specialist who is working on it.