Fuel Pump in tank e30

[nibbe30]

Hi all, My new, as in I just bought it, e30 318i coupe 1989, has a low frequency humming or droning sound, in cabin, when ever the engine is running. This sound does not increase with reving or speed. Does anyone think it's conclusively the intank fuel pump.

[Jamie8GTi]

without hearing it, its a job to say.. take out the lower half of the rear bench seat and put your ear against the inspection hatch (drivers side) you'll know if its coming from the pump or not straight away!

[Brianmoooore]

Pull out the fuel pump relay and link together pins 30 and 87 of its base, which will make the pump run continuously without the engine or ignition on, so allowing you to hear if that's the same noise.

P.S. Do you have a M50/52 (24 valve six, cylinder engine) in this 318, or have you simply posted in the wrong forum?

[Jamie8GTi]

Pull out the fuel pump relay and link together pins 30 and 87 of its base, which will make the pump run continuously without the engine or ignition on, so allowing you to hear if that's the same noise.

P.S. Do you have a M50/52 (24 valve six, cylinder engine) in this 318, or have you simply posted in the wrong forum?

whats the lowdown on the 24v's? to much for an m40 pump?

[Brianmoooore]

M40 pump is absolutely fine for M50's and M52's - they don't require a higher fuel pressure than M40 engines, and fuel consumption is much the same. Some S5x engines use a higher fuel rail pressure, which the standard E30 pump struggles to provide

[Jamie8GTi]

ah good thats what I thought!!