I need help
Thread Starter
Teching In
Joined: Jul 2008
Posts: 22
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From: orange texas
I need help I havent posted here in awhile due to deployments in the marine corps. I had the engine built for my s10. The motor is a lt1 with ported heads and a custom grind LE cam. My problem is i have no spark. I have replaced the coil, icm, distributor optispark, ect. I still dont havr any spark. Everything in the ignition has power and its 5volt references. I havehave check all the wires for continuity and ohmed all themy ignition wires. I have fuel pressure. Will the computer keep the ignition from having a spark. And if so what would be a good place to start?
TECH Resident
Joined: Apr 2010
Posts: 787
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From: T E X A S
where does the no spark start? like does the coil put out a spark or does it stop further down the line?
check the plug on the passenger side going into the top of the opti, if it isn't seated all the way it won't work, ask me how I know.
check the plug on the passenger side going into the top of the opti, if it isn't seated all the way it won't work, ask me how I know.
I havent posted here in awhile due to deployments in the marine corps. I had the engine built for my s10. The motor is a lt1 with ported heads and a custom grind LE cam. My problem is i have no spark. I have replaced the coil, icm, distributor optispark, ect. I still dont havr any spark. Everything in the ignition has power and its 5volt references. I havehave check all the wires for continuity and ohmed all themy ignition wires. I have fuel pressure. Will the computer keep the ignition from having a spark. And if so what would be a good place to start?
Just curious, what's the specs on the cam?
Thread Starter
Teching In
Joined: Jul 2008
Posts: 22
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From: orange texas
The coil does not spark. The cam specs is 270/276 510 lift 111. Lobe sep. +4 for nitrous. I look for a crank position sensor. My motor doesnt have one. I have a 95/96 msd opti. Ive bren tryin to trace wires. But of course it has a s10 harness and a camaro harness and i cant find a diagram to go off of. Does the driver in the computer go bad or does it have internal grounds guess ill just send the computer to pcm for less
www.shbox.com
That gives you the fbody wiring diagrams. You would have to match that with your s10 wioring, and I am only assuming you used the pcm from the fbody??
The PCM does have drivers in it that provide ground to some and it toggles voltage for others. It has to toggle from 0-5v to the icm for the coil to spark, so signal from the opti to the pcm to the icm to the coil back to the opti. it goes from signal to spark.
That gives you the fbody wiring diagrams. You would have to match that with your s10 wioring, and I am only assuming you used the pcm from the fbody??
The PCM does have drivers in it that provide ground to some and it toggles voltage for others. It has to toggle from 0-5v to the icm for the coil to spark, so signal from the opti to the pcm to the icm to the coil back to the opti. it goes from signal to spark.
