Originally Posted by Patryk1098

I have a (U.S.) 2005 X5 4.8is. I'm not certain of the production date -I haven't dug into that just yet.

I have been experiencing the same starting problem. If you're already familiar with it, please skip the following paragraph:

Problem Description:
In the winter / colder season (temps below 50F), once the car is fully warmed up, I park it for roughly 80-100 minutes. When I come back and attempt to start the car, it initially sputters very briefly as the engine cranks, then it simply continues to crank. The starter doesn't stop, but the engine isn't firing, just constantly turning over. I don't want to kill the battery, so I turn the key back to stop the starter. Repeated attempts provide no change, and depressing the gas pedal (or not) seems to have absolutely no effect. In fact, there appears to be no rhyme or reason as to why it starts, other than when I hear it start to sputter (very very lightly), I depress the gas and pray it "catches".

Important Additional Notes:
Once the car starts after having this issue, it runs fine and starts back up without hassle if turned off.

The car has cut out on my while stopped in traffic. No sputtering, no warning, engine just stops.

No fault codes were recorded when the starting problem occurred.

Fuel tank has been at varying levels; this happens on a full tank, near empty, and somewhere in the middle.

Fuel quality does not seem to be an issue (or at least I don't suspect it to be one since this seems to happen regardless of where I get gas). I've always run premium.

This never happened during warmer weather (I've had the car since August).

I leave the car parked outside (no garage).

The car never sputters while driving, idling, or any other time: There are no precursors to this problem.

There is no fuel smell when the car won't start (or otherwise).


After reading this thread, I brought my X5 to my local dealership. I explained the problem I've been having and that my research has suggested that updating the DME software might help. I allotted 2 hours for the technician to attempt to diagnose the problem. The service advisor (whom I believe is actually very knowledgable) mentioned that it could be leaking injectors, though if I don't have consistent fuel smell, they're not likely to be the cause. It could be fuel pumps (there are two, one in the fuel tank and one outside), fuel filter, etc. Or, it could be the DME as I've suggested.

They tested the external fuel pump and it behaved normally. The updated the DME software (there was an update to a newer software version) and suggested that if the starting issues resurfaces, that it may be worthwhile to test the fuel pump within the gas tank.

Thus far, the engine seems to run smoother all around. While the change is ever-so-subtle, I notice it most when the car is cold and on throttle response. The previous DME software had the car respond sluggishly when I attempted to depress the gas to accelerate. Now, the car seems to respond more quickly under both subtle and aggressive acceleration.

I don't think the DME update gave me any more power (though it might; after all it IS the engine management system), but it definitely made the engine run a bit smoother.

I haven't encountered the starting issue, but it has only been a few days. The next two months will tell.

Programming the DME and testing the external fuel pump can be done within 2 hours of labor -so don't let your dealership rape you. They may need the car for the day since the DME updates tend to crash ~70% of the time and require the update to restart. The actual software update can be run and left alone -and requires some time (so I'm told), but a technician doesn't need to waste time sitting and watching it.