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Tiger
03-19-2008, 07:45 AM
Crank position sensor... buy dealer only part. Don't buy aftermarket brand.
bardon1
03-19-2008, 08:40 AM
I am trying to troubleshoot a no start problem. I drove the car on Sunday. Monday would not start, It appears that I have no spark. I have tested the ignition coil and got .6 - .7 on the primary (manual says it should be .5). I got 6900 on the secondary (manual says 5k - 6k). Do you think these readings are far enough off to warrant replacing the coil. If not the coil, what else should I check?
M20Turbo
03-19-2008, 09:18 AM
Please tell us a little about the E34, 520, 525, 530, 535, 540, M20, M30,.... ect.
bardon1
03-19-2008, 10:08 AM
1990 e34 525i 300k+ mi distrib and rotor button replaced about 3 months ago, last major tune up (plugs, wires, coil) about 2 years ago.
525i winter driver
03-19-2008, 12:00 PM
I am trying to troubleshoot a no start problem. I drove the car on Sunday. Monday would not start, It appears that I have no spark. I have tested the ignition coil and got .6 - .7 on the primary (manual says it should be .5). I got 6900 on the secondary (manual says 5k - 6k). Do you think these readings are far enough off to warrant replacing the coil. If not the coil, what else should I check?
i have the same higher-than-the-manual readings on my ignition coil. i have some idle problems that i'm trying to troubleshoot but i don't think that's the problem there - my m20 has an occasional hot-start problem but starts every time cold. i would check fuel delivery also.
bardon1
03-19-2008, 12:25 PM
Crank position sensor... buy dealer only part. Don't buy aftermarket brand.

Would the crank position sensor prevent power from reaching the coil? Can I test this sensor?
Tiger
03-19-2008, 01:33 PM
No signal means no spark. Don't bother to test it... inspect it and make sure it is not rubbing on pulley teeth.
pingu
03-19-2008, 07:12 PM
Those readings sound good to me. On the primary, you can only measure resistance to within about 0.1 ohm so you're fine on the primary. On the secondary, the readings will depend to some extent on the type of measuring equipment you're using. But if you had any serious problems on the secondary (e.g. breakdown of insulation) then you'd be getting a resistance value that too low low, not a resistance value that's too high.

I reckon the problem is something other than the ignition coil - Tiger seems to have some good advice on this.