Hi guys,
Very proud I am with my 325i convertible. A very happy man I was indeed untill evil stroke my loved one. Out of nowhere the engine suddenly died. Like removing the key while driving.
The strange thing is, that the next day the car just started, but the same thing happend after 10 minutes. I've done some trail/error stuff and finally I found the problem!
The fuelpump seems to work for like a few minutes, and then it stops. When i wire if just after the relais it works properly. Now I could keep driving like this, but I just want to be sure of a few things.
Question 1: If I turn on the electric system with my wired situation (not start the engine) the pump already starts to work. Now I can't remember the pump working when I washed my car and turned on the radio. It seems to make sense to me that the pump starts to work only when the engine is working.
Question 2: Apart from the fuelpump trouble, the fuelmeter always says there is 60L in my gastank. I am aware of the non economical fuelcomsuption of the 2.5 l engine, so I guess ta connector is the spoiler. I wonder if the wire from the pump and from the fuellevelsensor are on a same connector? In that case that could be the problem?
Could some electrical bug be the problem? I wonder if the computer has a specific role in the activation of the pump.
Many thanks in advance!
greetings,
Koen
325i '91 fuelpump wiring/relay trouble (I guess)
Moderator: martauto
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Brianmoooore
- E30 Zone Team Member
- Posts: 49360
- Joined: Mon Jan 10, 2005 11:00 pm
Just made a comment on your other post, but now I've found this post, which answers the question!
If you are sure that the car behaves properly with the fuel pump relay bypassed, then the relay itself is most likely the problem.
Fuel pump relay is one of the three under a small cover near the air filter.
Q1/ You are correct that the fuel pump only runs when the engine is turning. The ECU switches on the fuel pump relay when it recieves a signal from the crank position sensor. Don't think there is a problem with this, because the signal is also used to trigger the ignition system.
Q2/ Wire to the pump and level sensor go through a plug and socket underneath the right hand side of the rear seat cushion. From there it goes to two seperate connectors on top of the fuel pump.
The pump is under an inspection cover, also under the RH side of the seat cushion. The level sensor unit is probably faulty. Lifts straight out of the tank after unscrewing the four small nuts on the top.
If you are sure that the car behaves properly with the fuel pump relay bypassed, then the relay itself is most likely the problem.
Fuel pump relay is one of the three under a small cover near the air filter.
Q1/ You are correct that the fuel pump only runs when the engine is turning. The ECU switches on the fuel pump relay when it recieves a signal from the crank position sensor. Don't think there is a problem with this, because the signal is also used to trigger the ignition system.
Q2/ Wire to the pump and level sensor go through a plug and socket underneath the right hand side of the rear seat cushion. From there it goes to two seperate connectors on top of the fuel pump.
The pump is under an inspection cover, also under the RH side of the seat cushion. The level sensor unit is probably faulty. Lifts straight out of the tank after unscrewing the four small nuts on the top.