[laurentium.ionescu]

Hi everybody,

I own an F30, n47d20c, 184hp, automatic and I have serious problems starting the car, it cranks for 5-10 seconds, 2 or maybe 3 times before starting. Sometimes it even starts after second attempt but stalls immediately.

Fuel quantity control valve already replaced, all 4 injectors were checked and are fine, HPFP has no metal shards.

I got two errors from which one appears even after DTC's delete:
249300 - Rail pressure monitoring on engine start: Rail pressure too low during engine start
(This one appears back after deletion)
25AD00 - Fuel quantity control valve, activation: Short circuit to earth.
(This is the part which I replaced and I still got the error).

The interesting part is that if I disconnect the Fuel quantity control valve it starts fine.

Only the start is problematic, after that the car runs fine, no power loss, no errors, nothing.

Does anyone has an idea about what is happening to it?

[kdog_x]

With 'short circuit to earth' being listed, I would check the wiring harness that goes to the control valve for any possible damage, maybe the insulation on one of the power wires is knicked /melted somewhere.

[laurentium.ionescu]

Originally Posted by kdog_x

With 'short circuit to earth' being listed, I would check the wiring harness that goes to the control valve for any possible damage, maybe the insulation on one of the power wires is knicked /melted somewhere.

Thank you, I'll ask the mechanic to check it.

[laurentium.ionescu]

Maybe it helps someone, after a BMW electrician (not mechanic) checked my car he said that he's 99% sure the problem is HPFP, I replaced it and the car starts fine now.

[kdog_x]

Good to know. Thanks for updating! Makes sense from the low pressure warning. Good that it didn't implode and send shrapnel into the lines, it's famous for failing in spectacular (and expensive) fashion.

[laurentium.ionescu]

Originally Posted by kdog_x

Good to know. Thanks for updating! Makes sense from the low pressure warning. Good that it didn't implode and send shrapnel into the lines, it's famous for failing in spectacular (and expensive) fashion.

Yes, I know, only problem was that first thing I checked when I bought the car was the HPFP just because I knew it's reputation for this kind of stuff and it was all right. Nobody expected just to be unable to make or hold pressure..

[laurentium.ionescu]

Hello again guys,

I’m back, the car has the same symptoms as before, same errors, I think I’m going to set it on fire.

Does anyone have any (new) ideas?

I already checked the wires that goes from ECU to the Quantity Control Valve and they’re fine.

Thank you in advance.