fuel problem

[ryderb1474]

Just bought another 91 325is. The owner said he put the battery in wrong and after he corrected it it wouldn't start. After swapping a bunch of parts including the crank sensor it still won't start. Its getting spark but no fuel. Fuelpump is good just won't turn on. Would really appreciate any help.

[street_127]

I just put a new fuel tank in and changed all the lines. The car wouldn't get fuel so I jumped the fuel pump fuse (it was fuse 11) and primed the system for a few seconds. After that it started right up.

When turning the key to the on position the fuel pump won't turn on, but when you turn it over the fuel pump should kick on.

Fuel pump relay is the middle of the three in the engine bay.

A fuel line could be switched

I'm still new to these cars so these are the things I encountered this past weekend when installing the tank. Sorry if I only state the obvious and I'm not much help. Best of luck! Fuel issues suck!

[ryderb1474]

Lol. Will be trying all your suggestions friday.

[nickmcc92]

I've also had a problem with my fuel pump relay after I forgot to unplug the battery.
It's the middle relay out of the 3 under the black cover. Near the fuse box

[ryderb1474]

Ok, got the car home. Fuel pump relay and fuse are GOOD. Replaced crank position sensor. Still won't start. After checking, fuel pump fuse is not getting power and relay is not clicking. Please help BIMMMER DOWN! BIMMER DOWN!!!!!!!!

[ryderb1474]

*update* went back out this morning to look at it with fresh eyes and noticed the my 5pin main relay felt real warm while all the rest of them where cold. Any idea why?

[jlevie]

If the ignition was off the main relay should have been cold. The main relay could be bad, or there could be problems elsewhere in the car's wiring/electronics.

[ryderb1474]

Damn......... this all started from the previous owner putting the battery in backwards. Has has never started again. But I do have spark.

[ryderb1474]

Replaced ALL relays and still getting spark and no fuel. Not even getting power to the 11 fuse. I'm lost now.

[ryderb1474]

Fuse in trunk is good, new cps, plugs, wires, cap and rotor. All relays are new. I have spark. Fuse 11is good but no power to it but the pump relay has power. I jumped power to fuse 11 and the pump came on but still woyldnt start. I need some help before I set this bitch on fire in the street.

[street_127]

Ok, so you'll need someone else to help you try this... Have them jump the fuel pump to the battery terminal at the front of the car through fuse 11. Let it run for a couple seconds and start the car, have them remove the jumper wire and see if the car will stay running. If the car actual starts and runs then you know your fuel lines are okay and it is most likely an electrical issue and not mechanical.

If you can't figure anything out with that try this check, it will lead you through all the possibilities! http://www.bavauto.com/newsletter/20...newsletter.pdf

Good Luck

[ryderb1474]

I think its gonna end up being an ECU gone bad. Anyone have a spare for sale?

[jlevie]

The battery being connected backwards could have damaged the DME, specifically the output section that controls the fuel pump relay.

[ryderb1474]

Shit! And that's the one part I CANT find local......

[jeffnhiscars]

IME hooking the battery up backwards will usualy blow the diode in the alternator. Since I believe there are a bunch of engine management functions that require the exciter wire from the alternator to be live, this could also be your problem.