Fuel pump will not turn - BMW Forum

Handymanbob · 08-12-2011, 05:29 AM

I changed out my engine and wiring Harness. I have all functions but no Fuel Pump. The engine will turn but no fuel to the injectors. I ran direct power to the pump and it pumps. I have power at the pump contacts.

brettski · 08-12-2011, 08:21 AM

Does the Fuel pump relay actually activate (for 2 seconds) when your turn the key to position II?
If you manually power the fuel pump and try to start the engine, will the engine start and run?

Handymanbob · 08-12-2011, 04:11 PM

I get no action from the the pump when the is turned.
I did not run the pump that one it was long enough to see if it will pump.

Handymanbob · 08-12-2011, 09:00 PM

Yes the relay did activate, I had my partner check for the clicking when i turned the key. I'm not getting fuel at the injectors. I almost wont to think my fuel regulator is bad. I took apart the fuel filter and lines and fuel was in the line but only up too the filter. The regulator line to the injectors are dry.

brettski · 08-12-2011, 09:45 PM

Try to disconnect the fuel line before the fuel filter and see if there is fuel being pumped to that point, have a can or similar container ready to catch the fuel. Some of the fuel filters have an inbuilt pressure regulator as well. If there is fuel getting to the filter, but isn't fuel getting passed it, try changing the filter and see whether it helps. If you aren't getting fuel to the filter when the pump is running, its either a kinked/crushed fuel line or a dud fuel pump.

Not trying to state the obvious, you do have fuel in the tank don't you??

Jack Dabsy · 08-13-2011, 07:09 AM

As brett says...
And maybe try running a live from the rear light cluster (lights on!) to the pump, just to test it !!

brettski · 08-13-2011, 09:15 AM

One other thought, not even sure its possible or likely. If the pressure reg on the fuel rail is seized closed, it may be creating an air lock on the fuel rail and not letting fuel actually reach the injectors. If the motor you have installed had been sitting around unused for a long time, the fuel may have evaporated from the fuel lines and the pressure reg could be stuck closed? Just a thought.

Handymanbob · 08-13-2011, 04:12 PM

Thank you for your help. I have power to the fuel pump connections it will not pump when I attempt to start the car. I did run a lead and the pump starts pumping.

Could it be a security feature with the key and the ECM not talking to the different Key.
Remember i did take the entire engine, wiring, ECM and fuel pump from the other car. I did the igintion switch and got no engine response just list in the dash. Changed it all back and got everything but fuel pump activation.

Handymanbob · 08-13-2011, 04:25 PM

The regulator is not attached to the fuel rail, it is located near the fuel filter independent system wired below but fuel line run connected to the reg.
The 96 318I has the Reg attached to the Rail but the 98 318ti has the Reg attached independent of the Fuel Rail under the car.

Jack Dabsy · 08-14-2011, 08:52 AM

There should also be a purge valve at the end of the fuel rail to disperse any air !!

Handymanbob · 08-20-2011, 09:19 PM

I ran the test from the rear lights and the pump ran with no problem. I have fuel at the rail, test the bleed plug and fuel shot out. Back to main issue what is causing me not get pump activation when key is turn. What do I check next or give me a list of possibilites.
Thanks for helping.

Jack Dabsy · 08-21-2011, 05:57 AM

Immobiliser?

brettski · 08-21-2011, 06:55 AM

I am not sure if the crank position sensor plays any role here. If the engine still is not firing when you manually power the fuel pump then are you injector activating at all? Any sparks on the spark plugs? May engine control module problems or as Dabsy sauggested an immobiliser?

Jack Dabsy · 08-21-2011, 07:46 AM

When you ran a live to the pump, and it worked, did you try to start her up with the live still connected at the pump?

Handymanbob · 08-21-2011, 07:40 PM

I ran the live wire to the pump and with still pumping i did attempt to start it and it won't start. I used starter fluid and it started for a brief moment. So yes i'm getting spark at the plugs. How do i check for immobiliser issues.

My next step when I can't take anymore is have pickup and taken to the shop. Then I'll pay out the rear for something simple because I couldn't find it.