525 stranded, need help >>and cause of trouble

[shogun]

here the story which might help someone in future:
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My '93 525i w/132,xxx miles wouldn't start for me Saturday, luckily, a shop was open, changed my fuel filter but said the fuel pump was about go, told me to keep it full of fuel to help and it would probably get me home to Dallas from Houston. It didn't, even after 'priming' the system, I suppose several times before starting (by turning key to on but not to start). So, I bought a fuel pump, felt like it was too big a job for me after filling the tank to the brim with fuel, took it to them, put in new one, and it still won't start. any ideas for me to give them to help- me get outta here? thanks,
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Are you sure its fuel related? What are the 'no-start' symptoms? Just keeps turning and turning and turning? Need info!
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not sure. Yes, just turning and turning over. They put in a fuel pump, but no start. He found there is no rpm signal, I believe he was saying, (code 26) no signal was going to the fuel relay either, guessing its the crank position sensor or computer ( he guessed). No, they aren't bmw specialists but they do appear to be very fair and aren't charging completely for all the time on this. To top it all off, now the sunroof won't close!!! Its only up in the 'vent' position and I can hear something trying to 'happen' behind the controls. What the heck? Yeah, I know it can be closed manually but the timing.....awfully strange.
So, does anything think it might be the crank position sensor? If so, where might it be?
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The crank position sensor on a M50 is bolted to the very front of the engine. The CPS itself is reasonibly easy to remove and replace, but the darn electrical connector for it is under the intake manifold, and is a bugger to reach. It can be done without removing the intake manifold, but it aint easy. And yes, if the CPS is dead, no power will go to the fuel pump.
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Guessing you have the M50 engine because there is no code 26 for the M20/M30. One of the position sensors is what activates the fuel pump relay. (Safety... no fuel if engine not turning.)
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Check fuseable link - ensure it is sound and clean.
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fixed!!!! Well guys, the fuel pump didn't fix it, but replacing Crank shaft position sensor did. I really went back and forth over the idea of removing the new fuel pump since I didn't feel like that was the problem, but after changing the fuel filter, the car started 4 more times in a few hours, didn't start again though, what's the freakin' chances of the cps and fuel pump going out at the same time???? I decided to keep it after it had been replaced for fear of something happening later on ( had a 300 mile drive to get home too).

[Mordan]

thx!

is that CPS issue as common with M20 as it is with the M50?

[Tiger]

On all BMW, CPS is a common problem. Especially you are over 100,000 miles.

[nirvana19]

CPS makes sense. My guess is they disconnected the battery with the sunroof open, which confuses the general module so when you try to close it you'll hear the click you normally would when it's already closed. I had the same issue when my sunroof was completely open after doing my headgasket, just manually closed it a few turns and then the car recognized that it was open and it worked. Probably the same happened with this car as there was no further mention.

[upallnight]

132,000 miles and you want to switch back to the old fuel pump because it wasn't the problem? What, are you ? My fuel pump crap out last winter and it ended costing me over a 100 bucks just to get the car tow back to my house. That includes the AAA members free tow for the first 10 miles.