LS2 engine swap wont start - please help
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Staging Lane
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From: Palm Beach Gardens, FL
LS2 engine swap wont start - please help I have an LS2 motor out of a ’06 Corvette with a 58 tooth reluctor wheel that I installed in my Panoz track car. I have a Holley 750 carb set up so I had to add the 58 tooth MSD carb ignition system to make the switch over from FI. Anyway, the car won’t start. I checked and am getting 12 volts to the MSD box, an getting 12 volts to the coil packs (which I got used on the forum, could be an issue), but I get no spark at the plugs. So any ideas? What resistance should I read on the crank sensor, the cam sensor and the coil packs? I’m thinking that is the only thing that could go wrong. The crank sensor is new from GM, the cam sensor came with the engine. I am told the jumper cable to the cam sensor needs to be deleted for the MSD box to work right, because it seems to reverse the wires to and from the connector and have tried to start the car with and without the jumper wire, but didn’t make any difference.
Help!!
Help!!
TECH Regular
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From: Sparta, Mo. in southwest Missouri
I think he mis-read your post. He apparently thinks you are working on an EFI engine instead of a carbureted engine. I don't have a solution for you, but I will suggest that you also post in the carb forum, if you haven't already.
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Staging Lane
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From: Palm Beach Gardens, FL
I have an LS2 ’04 Corvette engine with a carburetor in a Panoz track car. It has a 58 tooth reluctor wheel (which I have counted to make sure) and I have installed a 6012 MSD carburetor ignition system.
The problem is that I am not getting any spark at any of the cylinders.
To trouble shoot, I have replaced both the cam and crank sensors (gray).
I am getting 12 volts to the MSD box.
I am getting 12 volts to the coils.
I am getting 5 volts to both sensors.
I have the step retard unhooked.
I have the MAP unhooked.
When I crank the engine, with or without the spark plugs, I do not get a tachometer reading on the lap top. Engine is turning over at a good speed.
I also get a “no crank signal” on the lap top. This is why I replaced both sensors.
I am getting ~ 4.5 volts return from the cam sensor. (using a multi meter, so don’t know how good that volt value really is) back to the box.
I am getting ~1.3 volts return from the crank sensor. (using a multi meter, so don’t know how good that volt value really is) back to the box.
I am only getting ~0.05 volts to the coil packs to fire the coil from the box (using a multi meter, so don’t know how good that volt value really is)
So, I’m stumped. The box is new, but can it be bad?
What else would you suggest?
The problem is that I am not getting any spark at any of the cylinders.
To trouble shoot, I have replaced both the cam and crank sensors (gray).
I am getting 12 volts to the MSD box.
I am getting 12 volts to the coils.
I am getting 5 volts to both sensors.
I have the step retard unhooked.
I have the MAP unhooked.
When I crank the engine, with or without the spark plugs, I do not get a tachometer reading on the lap top. Engine is turning over at a good speed.
I also get a “no crank signal” on the lap top. This is why I replaced both sensors.
I am getting ~ 4.5 volts return from the cam sensor. (using a multi meter, so don’t know how good that volt value really is) back to the box.
I am getting ~1.3 volts return from the crank sensor. (using a multi meter, so don’t know how good that volt value really is) back to the box.
I am only getting ~0.05 volts to the coil packs to fire the coil from the box (using a multi meter, so don’t know how good that volt value really is)
So, I’m stumped. The box is new, but can it be bad?
What else would you suggest?
So Ducky, is your motor an '04 or an '06? Details in post #1 and post #6 are different... Maybe you are running the wrong cam sensor setup? I have an '04 setup and it's a 24T reluctor with a rear mounted (cam driven) cam sensor on a '6010 box. IIRC, the '06 does have a 58T reluctor and the cam sensor is driven off the cam gear (not sure if it's a 1x, 2x, or 4x). Could be the difference...
