[sherbo]

Hi all,

I got a 2011 X3 xDrive28i (with a 3.0L N52 Engine) 2 weeks ago, with 46k Miles on it.

In the morning I was starting the car, it cranked but engine did not start. I tried the next day, now the engine is starting for half a second then stalling immediately.

Here's the troubleshooting that I did:

Fuel:
a) Turned on ignition (but not engine), fuel pump terminals read 0V and no sound.
b) Started engine, pump terminals read 10-11V (Too fast for voltmeter to catch) for half a sec then engine stalls/pump voltage goes to zero
c) Pump resistance reading is (0.7 - 3 Ohmm) depending on probe placement

I have a few questions...
1) During step #a, I thought the pump should go on for 3 seconds but I'm not getting that. Does it always do this? Or maybe it's not turning on because there's already fuel primed in the line?
2) Any way for me to detect if the pump is dying and stalling the engine, or is it the other way around (Is the car actually turning the pump off) ? Should I feed +12V to the pump directly and see if it runs for 5 seconds
3) Since the engine is running very briefly, is it safe to eliminate spark issues? (I don't have the spark plug tool but I'll buy it if there's a good chance there).
4) I've ordered a ELM327 bluetooth dongle to check if there are any errors. But is it even possible to have faults when my iDrive is showing no issues?

Finally, appreciate any guidance/advice on what to do next.

Regards,
Sherbo

[ba ba boosh]

Battery is dead, this happened on my E90.

[sherbo]

ba ba boosh,

Thanks for your reply. Just to make sure I'm getting this correctly,
You had a dead battery, yet your car cranked & started ? That sounds really weird. I mean cranking the engine requires a great deal of energy?

Regards,
Sherbo

[ba ba boosh]

Originally Posted by sherbo

In the morning I was starting the car, it cranked but engine did not start. I tried the next day, now the engine is starting for half a second then stalling immediately.

That's basically what happened in a nutshell. But I am no master mechanic by any means. Check when the battery was last changed. My old E90 330i would start for a split second then die, I changed the battery and it was fine.