HELP!!!!! M20B25 conversion, no spark!! ****SOLVED****

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Danvl1991
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Sat Feb 20, 2016 10:33 pm

Am at my wit's end, spent the last 5 hours trying to figure out why my m20b25 hasn't got any spark, I'm getting a live to the coil with the ignition on but I'm not getting a pulsed earth, everything is plugged in as it should be, ecu swapped over ect, but for the life of me I can't figure out why it has got no spark, the engine came out of a previously converted 316 the same as mine about 6 months ago and it was running spot on, is there anything that isn't on the wiki (I've read it about 4-5 times) that I need to do? Or does anybody have any idea what could cause loss of spark? Tia
Last edited by Danvl1991 on Mon Feb 22, 2016 9:24 pm, edited 1 time in total.
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Brianmoooore
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Sat Feb 20, 2016 10:57 pm

I'm fairly sure the wiki mentions the possibility of a failed crank position sensor fairly early on in the text! Is the fuel pump kicking in when you crank the engine?
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Danvl1991
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Sat Feb 20, 2016 11:31 pm

I havent got a fuel pump at the moment as it's gone from a carbed engine, I'll have a look, is that in the m20 conversion wiki?
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Brianmoooore
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Sun Feb 21, 2016 12:06 am

Just connect a bulb to the pump wires and check that they go live when cranking.
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Danvl1991
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Sun Feb 21, 2016 12:13 am

I'll give that a go tomorrow bud, cheers
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Danvl1991
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Mon Feb 22, 2016 2:45 pm

Little bit more info, there's no injector pulse, no coil pulse, the fuel pump relay kicks in when I try and start it, I've scopped out the crank sensor and that's working, checked I've got lives and earth's to all the pins that should be at the ecu and that checks out ok, really stuck for ideas now :/
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Danvl1991
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Mon Feb 22, 2016 9:27 pm

Finally got to the bottom of it, after testing wires, earths, lives ect ect, everything tested fine so i decided to open up the ecu and VIOLA found a burnt out track, jumped the track with a small wire, chucked some easy start down the intake (no fuel system yet) and she fired :D :D :D
jimbom30cab
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Mon Feb 22, 2016 10:36 pm

Nice job !!
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