318i- Fuel pump/tank problems?

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BenG
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Post Sun Jul 05, 2015 9:53 pm

My 1988 318i seems to be having some running problems which are steadily getting worse and worse.

Main problem is that when going round roundabouts/corners slightly quickly power drops off completely, wait a second or two and it runs ok again. I know this is fuel starvation.

Recently when going in a straight line the car wouldn't rev properly, it would get to near 4000rpm and just stay there not gaining revs. It stayed like this until I turned it off for a minute and then restarted and it revs happily again.

It does this with any amount of fuel. It also has begun getting very slightly lumpy at idle and almost kangarooing at low speeds and revs.

I have replaced the fuel filter ( which was pretty rusty), taken the in tank fuel pump out and cleaned the mesh filter, tank doesn't look in a great way (rust present).

Any ideas what could be the problem? possible fuel pump fault, but why would it cause problems around corners?

Many thanks



:D :D
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Brianmoooore
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Post Sun Jul 05, 2015 10:40 pm

Have close look at the convoluted rubber hose between the air filter/AFM and the throttle body assembly. I think you may find a split in it, that opens or closes as the engine moves around under cornering.
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BenG
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Post Mon Jul 06, 2015 6:20 pm

Just checked all around the pipe and all is intact.
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bosers
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Post Mon Jul 06, 2015 7:08 pm

Could be water in bottom of fuel tank, that can cause rough running when cornering. My E30 had a drain plug in its original tank, not sure if all do but could be a good place to start.
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BenG
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Post Tue Jul 07, 2015 11:10 pm

Good shout, i'll drain it and see what comes out. Thanks

Any other things I could check?
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Brianmoooore
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Post Tue Jul 07, 2015 11:52 pm

Use a hex socket in the drain plug, and a pair of grips around the outside of it, at the same time.
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BenG
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Post Mon Jul 13, 2015 6:11 pm

Had no luck with the drain plug, was seized solid... :(