85 bmw 735i-- won't start up--it will crank over

it will turn over fast but won't start..12v coil has fire on both primary post but no fire at the secondary post that links the distributor. fuses good.fuel delivery good. got any suggestions.
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Check the battery voltage; I've seen them turn over but be too weak to give an adequate spark. Check coil output.
Might help if you mention the model and engine.
FloydR
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wrote

Er see subject - 1985 BMW 735i - so it is an E23 with an M30 engine.
Charge up the battery with a charger and see what happens.

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thanks, i've tried another coil and new battery,
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Dead crank position sensor? This little sucker killed my M20 with exactly the same symptoms. No spark would cause me to look at the main relay and the position sensor. The sensor tells the ECU when to fire the coil...
On Sun, 22 Jun 2008 20:20:02 -0500, "bojames"

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thanks mike,for tickering my brain, hot diggie dog, it was the main relay, on the passenger side firewall, in the engine compartment, a 5 prong square relay, just above the hood latch
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thanks guys, mark and floyd
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