2003 E53 3.0d M57 crancking but not starting issue

[wpoll]

Here's the fuel pressure testing instructions for the M57TU - while the details are a little differnt the basic process of elimination may apply to your engine...

https://www.newtis.info/tisv2/a/en/e...ontrol/2wZTOhh

By the way, I'd avoid trying to start the car via some of the methods described above - even if it fires (which I doubt) it's not going to tell you anything useful and it could lead to bigger issues.

If pressure tests indicate low fuel rail pressure, you might need to look at the HPFP and the pressure regulating valve on the back of the HPFP.

But as I said earlier, without scanning for error codes you're just going to have to make guesses...

[Clavurion]

Originally Posted by wpoll

By the way, I'd avoid trying to start the car via some of the methods described above - even if it fires (which I doubt) it's not going to tell you anything useful and it could lead to bigger issues.

Of course proper diagnostics and monitoring live status values would be the best way proceed. But if you can start the engine simply with some aid of brake cleaner it usually runs normally after it has started. So actually it tells quite a lot meaning a pure rail pressure problem on start up. And in this case most likely caused by leaky injector (measure injector leak off) or failed o-ring on rail pressure regulating valve (at the rear of HP pump).