HELP, LS2 into a 74 Vette won't start
03-02-2012, 12:30 PM
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HELP, LS2 into a 74 Vette won't start I have swapped a 2008 SS Trail Blazer LS2 into a 74 corvette and have tried to start it but it won't start. I have fuel pressure at the rails, 12v at the coils on the + side to ground, But I only have 5 Volts at the crank and cam sensors when I think I am supposed to have 12v, am I right? What could be the reason for only having 5V at the cam and crank sensors to ground?
My thought is the the ECU is not receiving any signal from the crank sensor, there fore the ECU will not fire the coils or injectors.
The ECU has had the Vats removed, and the ECU switched power is hot with switch on and switch cranking, so the ECU and controls have 12v with out interruption, Except the cam and Crank sensors, they only have 5v to ground.
Any Help is much appreciated.
Riggs.
My thought is the the ECU is not receiving any signal from the crank sensor, there fore the ECU will not fire the coils or injectors.
The ECU has had the Vats removed, and the ECU switched power is hot with switch on and switch cranking, so the ECU and controls have 12v with out interruption, Except the cam and Crank sensors, they only have 5v to ground.
Any Help is much appreciated.
Riggs.
03-02-2012, 03:24 PM
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I don't have a live meter/programmer to test that. I tried to test the crank sensor, but with it being hard to get to with the starter in the way, I got lazy, dropped the starter and tested the crank censor lead to ground and got 5v on both power in, and signal out. I also got the same thing at the cam sensor. Does 5Volts seam right, or should it be 12Volts? After looking back through some of my build photo's I seen the double roller timing chain was not for a 4X cam sensor, My motor is the 58 Tooth wheel/4X cam, Trick Flow is sending me a new Cam gear to replace that. Would this be the clause of the motor not starting, No spark or injector action. Would an LS start with the cam sensor unplugged, Just wondering because the cam gear I have is for a 24 tooth type 6.0, so the cam censor is not able to read any thing from this type of cam gear, and I thought it would act the same way if the cam sensor was unplugged, feeding the ECU no signal.
Riggs
Riggs
03-11-2012, 09:06 PM
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What scanners can I use to at least see live data of what the motor and sensors are doing. What the least expensive unit that gives good scanning info for a motor with unknown starting problem.
The motor is still dead, no sign of firing, power at the Fuel injectors and coils, but no signals to fire them.
I am looking to buy the HP tuner, but not sure if I need tuner more so than a live scanner.
Riggs
The motor is still dead, no sign of firing, power at the Fuel injectors and coils, but no signals to fire them.
I am looking to buy the HP tuner, but not sure if I need tuner more so than a live scanner.
Riggs
