I have a very weak spark at the spark plugs,help!

1989 CHEVROLET CAMARO
180,000 MILES
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RACERPS
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Have 12vlts at the coil and have 12vlts on both sides of the two wire connector at the module.I have checked out the coil and module and they are good.But have changed them anyway,and new cap,rotor,spark plug wires and plugs.Have checked conunity at the 4 wires from ecm to module and they are good.Thank-you for any help.It is a 2.8l manual
Aug 25, 2011 at 7:43 PM
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KHLOW2008
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Weak sparks are usually caused by bad ignition coil. Is the replaced coil of the same specifications? Are the connections correct? Have you checked the engine to chassis ground connections?
Aug 26, 2011 at 12:27 PM
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RACERPS
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The coil was car specified.Connecters only plug in one way,yes.removed and cleaned terminals,didn't look bad.Didn't help any ! I was also thinking it a ground problem,but i guess not.Still at a lose!!!
Aug 26, 2011 at 8:00 PM
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RACERPS
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Coil is what it suppose to be.Connections only go on one way.Grounds have been all cleaned,at least the ones i can see.Still stumped and lost!!!
Aug 26, 2011 at 8:05 PM
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KHLOW2008
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Are you sure it is the sparks that is causing the non starting?

Have you checked the compression?

Was anything done prior to this occurring?
Aug 27, 2011 at 11:52 AM
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RACERPS
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Thank you for the replies. Still should have spark regardless of compression.No,it was running and driving before.Does anyone know if the VATS system will will let the engine turn over and not start or it won't let the motor turn over at all.The system was by-passed before I bought it.
Aug 29, 2011 at 2:32 AM
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KHLOW2008
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You do not have sparks or have weak sparks? Both are different problems.
Aug 29, 2011 at 1:10 PM
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RACERPS
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very weak spark
Aug 29, 2011 at 6:14 PM
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KHLOW2008
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Do you have internal or externally mounted coils?
If all things fails, restart all over from the basics.

Though you have relaced the ignition coil, give it a test. Check the coil resistance, etc.

Try attaching a jumper cable between battery negative terminal and engine.

The VATS can cause non starting by not pulsing the injectors. Check to see if the injectors are pulsing.
Aug 30, 2011 at 5:35 AM