Tune-Up gone bad
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Tune-Up gone bad
So I have over 100k on the car and decided it would be a good idea to do a tune-up. Got a water pump (bearings were bad so glad I picked one up), spark plugs, plug wires, MSD coil, fuel filter and opti. Installed everything. That fuel filter is a pain. And now it won't start. It's something ignition. I have spark out of the coil, but not to the plugs. Is it possible I blew up the control module or installed the opti wrong. Is there a way to test the control module or which part it could possibly be?
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If you have spark from the coil but none to the plugs it indicates a problem with the cap or rotor. Did you remove the cap to inspect before you installed the Opti?
Last edited by toptechx6; Aug 2, 2010 at 07:07 AM.
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What year is your LT1?
early years its easier to put the opti on wrong because its a missing tooth on the drive and a filled gap on the opti. If it didn't just "pop" on its probably off.
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One of the steps I did when I changed the opti is to leave the water pump off, everything else hooked up and start the car. Its only going to run a few seconds.
What year is your LT1?
early years its easier to put the opti on wrong because its a missing tooth on the drive and a filled gap on the opti. If it didn't just "pop" on its probably off.
What year is your LT1?
early years its easier to put the opti on wrong because its a missing tooth on the drive and a filled gap on the opti. If it didn't just "pop" on its probably off.
Good point I will re-check that too. It's a 94 and yes it has keyed teeth.
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So just to confirm, were you having to replace ICM's or did just changing back to GM coil fix it? Replacing an ICM or coil is much easier than getting to that opti.
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I replaced both the ICM and the coil at the same time so I can't answer that for sure. Sorry. The ICMs are finicky about voltage. The OE coil is more than enough spark for your motor. With the MSD coil I seemed to have my fair share of ignition problems.
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How far out of the coil? Did you check to see if you had spark going into the opti at the opti end of the coil wire? The opti end of the coil wire can be a pain to get all the way in sometimes.
I replaced both the ICM and the coil at the same time so I can't answer that for sure. Sorry. The ICMs are finicky about voltage. The OE coil is more than enough spark for your motor. With the MSD coil I seemed to have my fair share of ignition problems.
I replaced both the ICM and the coil at the same time so I can't answer that for sure. Sorry. The ICMs are finicky about voltage. The OE coil is more than enough spark for your motor. With the MSD coil I seemed to have my fair share of ignition problems.
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Opti's have been know to be bad out of the box too. What kind did you get?
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Got one off ebay because they said it had a warrenty, so I figured it must be ok. Ill get a new coil and ICM and see how that goes first.
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Got her started last night. Lesson learned. I took the ICM to the auto parts store to have it tested. It tested bad. Put the new on in (along with a normal coil) and it started right up. Mind you the car ran fine before the tune up. The guy at the auto parts store said not to mix MSD ignition stuff with stock stuff. He stated he has seen this issue before when customers add MSD coils and took out the ICM. Now just have to figure out what codes I am throwing. Have to research the paper clip more.
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Got her started last night. Lesson learned. I took the ICM to the auto parts store to have it tested. It tested bad. Put the new on in (along with a normal coil) and it started right up. Mind you the car ran fine before the tune up. The guy at the auto parts store said not to mix MSD ignition stuff with stock stuff. He stated he has seen this issue before when customers add MSD coils and took out the ICM. Now just have to figure out what codes I am throwing. Have to research the paper clip more.
http://forums.corvetteforum.com/show....php?t=1994993
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Crank it up and let it idle. Pull each injector plug off until you find the one that doesn't change the the rpm of the motor. Then you can start checking that cylinder to see what is wrong. Most likely a wire or bad plug. Could even be a injector.