I need help with my 1994 BMW 318i…I ran out of gas and even after putting gas in it wouldn’t start…So I replaced the fuel filter and fuel pump relay then it started up again. Well after I turned Ed the car off it wouldn’t start again so I replaced the fuel pump and I still can’t get this thing to start. Any help would be greatly appreciated thank you
Have you confirmed the engine is getting fuel to it?
I don’t bear the fuel pump turning on at all but it is brand new…Not sure if it could be bad spark plugs or a bad coilpack?
Well if the fuel pump isnt on then it obviously wont get fuel. Check for power at the fuel pump and if there is none check back further on the wiring until you find where it isnt getting through.
It had power at the plug that’s why I am confused. I am no mechanic by any means but I can do simple stuff like the three things I did.
The possibility of a faulty fuel pump out of the box is small, but you may have been unlucky. If you are very sure it isnt turning on but has power, the problem could lay in the wiring between the connector and fuel pump. If you hook up a volt meter on the ohm setting to the fuel pump, do you get a reading? e
Check if fuse #15, 15 amp for the fuel pump, located in the front power distribution box located under the hood is blown.
While I agree the chance of getting a bad one is small, my shop did have two bad Delcos right out of the box or so they said. Yeah but if the pump isn’t running, that’s your problem, not spark plugs. Need to figure out why the pump isn’t running. Running a pump dry can ruin it though.
How about the ground?
That is also 3 things that might not have been needed. Throwing parts at a problem is seldom the answer.
My diagram says fuse #18 I replaced it with no luck
If you have voltage across the pump leads, the fuse is OK.
Do you actually have voltage across the pump leads? or just high to ground? there is a difference.
No starts – especially if they occur immediately after something simple happens like running out of gas – are almost always caused by lack of fuel or lack of spark. Checking for spark at a spark plug during cranking is the easier of the two. If you get a good healthy spark, check the pressure at the fuel rail next.
Other possibilities if spark and fuel pressure is ok
- check all the fuses, both in the passenger compartment and the engine compartment
- the cat can sometimes be damaged when you run out of gas, might have to temporarily bypass it as a test
- sometimes the engine can get severley flooded when working on the fuel system. I had this happen to my old VW Rabbit one time, spark ok, fuel pressure fine, wouldn’t start no matter what I tried. Removing the spark plugs showed the tips wet with fuel, so I cranked the engine a few times with them removed, then let the car sit overnight with the spark plugs removed to let any fuel in the cylinders evaporate. Next day I installed the plugs, started right up.
I didn’t bear the wiring schematic to death but here’s a few leads. It may help to sort things out a little and put you on the right track.
Fuel pump relay - hot red/white from main relay. (part of trigger circuit)
Brown/green ground through ECM (part of trigger circuit)
Red hot from battery to fuel and main relays
Green/violet from pump relay to fuse 11 - in between pump relay and pump. (Fuse is only a 7.5 which seems a bit weak for a F.I. pump)
Brown from main relay grounds through ECM. (part of trigger circuit main relay)
Red hot from battery to main relay (part of trigger circuit)
Hopefully the schematic is correct and more hopeful this may help in some small way.
flooding problem was happening a lot for me on old carburator cars, so I can imagine it to be plausible here
I might imagine a “lazier” method to “force-dry” engine after flooding: disconnect fuel pump fuse and crank it for several seconds, several times with full throttle open to purge it with air, then get fuse back and try starting. in this case one would not need to remove spark plugs.