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Old 11-04-2012, 03:14 AM
robertobaggio20 robertobaggio20 is offline
Location: earth
Join Date: Oct 2009
Posts: 3,403
Mein Auto: car
Originally Posted by Philipe525i View Post
Hi robertobaggio20

I will do and thank you. I have been driving my 525i for about 8 years now and have had to do some repairs already. I am a boffin at replacing the water pump as mine has gone about 3 times already and what took me the whole day to fix the fist time now only takes about an hour. This no start problem however is a new problem for me .

Well then please replace any one of the 3 items on the list that you have not done.

Secondly, you'll need to replace the water pump (use the composite metal impeller version, $50-60 at O reilly's online ) and the thermostat. For good measure, purchase a new bleed screw and a new rad cap (keep the old ones as spares). Double check that your auxiliary fan runs at both speeds, and ensure that your coolant temp /aux fan sensor is working correctly. All of these constitute the common overheating issues that occur for our E34s. That being said, overheating is not all that common.

I've recently realised that non-silicate HG in a bottle products such as steel seal and duraseal would be useful methods to suppress HG problems. All old cars and not just the E34, could succumb to HG failure due to its sheer age and mileage. The products concerned are not cheap at $100 for 6 cylinder cars, so you might want to think about it abit. For more details, please see :

As to no start problems, these are the UNcommon ones :

1. Clogged fuel filter.
2. Bad DME.
3. Bad fusible link (located next to the battery).
4. Bad battery.
5. Failed EWS system.

#3 and #4 do not apply to you as your car is still cranking away. #5 does not apply as your ride did not come equipped with EWS in 1991.

Please download the manual, read through the sticky thread, and check out a few of the no start issues (you can even pm the original posters (op) directly for advice) and proceed from there. Your research time could take the better part of one day, but it is time well spent as you'll learn many things that will be useful to your baby for the long term, I'm sure.

Please keep us updated on your progress.

As to this situation per se, you could check the crank sensor's ohm settings with a digital multimeter to see if they are within specs. They should be within 500 ohms or so. The Bentley manual, if it describes the ohm figures as 1000+, is wrong....reduce it by exactly 50% and see if you've got it right.

THe bentley manual will also indicate the correct pins on your fuel pump connector for you to test for current. Also test the corresponding metal prongs on the fp itself for continuity. If you have no continuity, you've got a dead pump. And even if you have a good pump, please have it replaced, it will die pretty anytime now *as I'm sure you'll agree after scanning the numerous no-start threads in the archives).

Good luck.


Last edited by robertobaggio20; 11-04-2012 at 03:16 AM.
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