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Really need eeryones help

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Machzzzz1

New member
Hi guys I'm hoping someone here can shed some light.
I just changed engines in my 1999 grand prix. Put the new engine in and everything went perfect. Go to fire it up and nothing. So I found out I have no spark, I hook up the scan tool and see that when cranking it shows rpm (and the tach bounces).so I assume my crank sensor is working. Then I notice that the wiring harness that goes from the icm to the crank sensor looks crushed, so I replaced that, still no luck. So after checking all the obvious fuses I conclude that it must be the icm. Well I just bought a brand new one and after crossing my fingers and turning the key I still have no spark. The car has been sitting since august, I've got no idea why it won't spark. I've checked the icm ground and it seems good. I've got a rpm reading so I guess my crank sensor is working. Please help me.
 


Machzzzz1 said:
Hi guys I'm hoping someone here can shed some light.
I just changed engines in my 1999 grand prix. Put the new engine in and everything went perfect. Go to fire it up and nothing. So I found out I have no spark, I hook up the scan tool and see that when cranking it shows rpm (and the tach bounces).so I assume my crank sensor is working. Then I notice that the wiring harness that goes from the icm to the crank sensor looks crushed, so I replaced that, still no luck. So after checking all the obvious fuses I conclude that it must be the icm. Well I just bought a brand new one and after crossing my fingers and turning the key I still have no spark. The car has been sitting since august, I've got no idea why it won't spark. I've checked the icm ground and it seems good. I've got a rpm reading so I guess my crank sensor is working. Please help me.
Click to expand...

Change the Cam Sensor.
Coolant seeping into the cylinders is what kept my car from running after it had been sitting. Lower Intake Gasket if you have coolant sitting on your pistons.
 
Ok, so you see bouncing on the tach. Did you unhook the pcm at all? If so, please check it.

I'd need to look over the info again, but a cam sensor being unplugged or bad gives you a 1 in 6 chance of starting. You would have started by now.
 
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