No start!

Post your E12 technical questions and comments here. Please, no off-topic posts.

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oceancab
Posts: 15
Joined: Thu Oct 17, 2013 11:45 pm
Location: Seattle

No start!

Post by oceancab »

Yesterday I decided to test out my alternator, so i connected my voltmeter to the battery with the car running and turned on everything. Shortly after, the voltage dropped to about 12.9 from 13.7 and the car died. When I tried to start it back up again, it wouldnt start. The engine just cranks and cranks with no hint of starting.

Would it be possible that some of the wiring got fried from having an increased electrical load? The car was running perfectly fine before.
darrylrevok
Posts: 9
Joined: Fri Feb 01, 2013 4:15 pm
Location: Ontario, Canada

Post by darrylrevok »

Is the alternator on your car the original Bosch one? I recently had to replace my alternator in my '78 530i because a friend of mine was helping me install a new battery and (GASP) somehow we managed to hook it up backwards, subsequently frying the alternator. If yours is the Bosch alternator, it could be the voltage regulator. BTW, if you'd like a replacement Bosch alternator for your car, check Rockauto.com. I believe they have a couple refurbished ones for very good prices in stock on there.

-Chris
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Mike W.
Posts: 2889
Joined: Wed Aug 30, 2006 12:12 am
Location: Sonoma County

Post by Mike W. »

Unlikely you fried anything, but I'd have to see just where, what got connected. If it was connected correctly it would not hurt anything.

Alternators very rarely fail, regulators sometimes do. Not a lot, but some.
Mike W.



02 525ita. Wife's, aka grocery getter
02 530i. New to the fleet, 3 pedals.
03 QX4, AKA the Datsun. Finally got the 4WD vacationmoble to stop smoking.
07 Xterra. Still on the DL, a purchase from hell.
oceancab
Posts: 15
Joined: Thu Oct 17, 2013 11:45 pm
Location: Seattle

Post by oceancab »

Well...the alternator's new.

The engine just seems to die by itself after it's idled for a couple minutes, after which it stops starting. I'm confident that there is no spark, and the coil only reads 4 volts with the key in the on position.

Not quite sure where to go from here, the car started after it had been sitting a while, and decides to call it quits at operating temp?
Danval
Posts: 87
Joined: Sat Dec 21, 2013 7:01 pm

Post by Danval »

Wow. I starteda post like this a couple weeks ago. Having almos exactly the same simptoms. Hope we can figure something out. Ill stay alert.
oceancab
Posts: 15
Joined: Thu Oct 17, 2013 11:45 pm
Location: Seattle

Fixed it!

Post by oceancab »

Ah well, turns out that he HT wire was grounding against the air box, causing there to be no spark.

The distributor wire still crackles though, and it have me a good jolt when I touched it...

Where's a good place to get a good cheap set of plug and HT wires?
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