1994 BMW 318 Overactive fuel oump

1994 BMW 318
210,000 MILES • 4 CYL • 2WD • MANUAL
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HELLRAZOR_1
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I was leaving for work and noticed that my fuel pump was just humming away, for how long I'm not sure. Regardless, it pumped a full tank of fuel out of the car. I had to remove spark plugs to relieve pressure to allow the engine to crank over. Cleaned and replaced them, but now it will not start. Any clue why the pump kicked on to begin with, and what I need to check for as to why it's not wanting to start now. The car was running beautifully until the fuel pump got excited, couldn't have ran any better, now she just won't start.
Mar 30, 2008 at 10:04 AM
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DOCHAGERTY
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I am concerned as to where the fuel went, do you know? If it pumped it into the motor, there is something going on here. Fuel pump relays sometime get stuck although I have never seen one get stuck on. The strategy used for fuel injection is to pulse width modulate the injectors to spray a finite amount of fuel into the cylinder(s) and injection should not be occurring when the key is removed. Repost or send me a PM if needed
Apr 3, 2008 at 12:43 PM
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HELLRAZOR_1
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Well, after further troubleshooting I had no spark and started to trace back from the plugs to the coil. Curiousity got the better of me and I opened the compartment that houses the DME and guess what I found. You got it, about a gallon of water poured out of it. Appearently having the DME submerged under water isn't a good thing, imagine that! I'm gonna assume that is what made the pump act up. The drain got clogged, (too small a drain) a design flaw the was taken care of on the '95 models. Cheapest new one I found was $1200.00, needless to say I turned it over to my insurance company and she is now in the hospital in Austin, Texas getting repaired. Should be ready by mid-week hopefully. Oh, the fuel went into the motor, air cleaner, and eventually the driveway. I did notice the both the fuel pump and DEM relays clicking wildly, and the injectors also clicking again with no key in the ignition. I guess the water in the DEM shorted everything??? Even though I'm letting the trusty BMW tech tackle this issue, I still am very curious if the water filled DEM is in fact the cause of the fuel pump malfunction. Regardless, thank God for full coverage insurance, the comprehensive clause covers it since I believe it was the rain storm the night before that filled the DEM up with water.
Apr 4, 2008 at 1:08 AM
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DOCHAGERTY
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You found the issue, and yes, water in the DME will cause problems every time. Let us know the out come.
Apr 4, 2008 at 10:28 AM
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DIAMONDGOLDSILVER
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I am concerned as to where the fuel went, do you know? If it pumped it into the motor, there is something going on here. I still am very curious if the water filled DEM is in fact the cause of the fuel pump malfunction. Regardless, thank God for full coverage
Apr 4, 2008 at 12:38 PM
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