Runs Awesome! But won't start first try
 

My 2000 X5 4.4i has never run better since I changed all the timing chain guides and rebuilt the VANOS units with the Beisen kit.

The only problem is, it takes two or three times to start it! It cranks but nothing happens. I've already changed the crank sensor to no avail. It has always done this intermittently so it doesn't have anything to do with my work.

I hear the pump running to prime the fuel system.

No codes.

Any ideas?

:dunno:

I've noticed if I turn the key off and on about 5 times it starts on the first try. Anyone know what this is??

This issue had happen to me a few times since I own my X (11 months of ownership). Not as often as your and I'm wondering why too. Let me know what you found out.

Could be fuel pump is going bad. Check pressure at fuel rail, should reach full operating pressure in about 2 seconds after key is turned to the run position.

I don't know if all BMW's have a similar design, but there is a check valve in the pump that goes bad well before the pump goes bad. Allows the fuel line to depressurize when pump cuts off.

I'll check the fuel pressure at start up.

See the 4.4 long crank thread I just bumped for details on what the readings should be and troubleshooting.

I THINK it is fixed! It has started and run the first try probably 20 or more times now. I replaced the fuel filter/regulator and that was the problem apparently.

Most likely the regulator, but now a days the regulator is included with the fuel filter. If you smell gasoline in the vacuum line that connects to the regulator that means the diaphragm is torn.

Yeah I posted that I replaced the fuel filter/regulator and that fixed it. Its been several days and countless successful starts so I'm calling it good.:thumbup: