5.3 standalone harness no spark
#1
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5.3 standalone harness no spark
so im not sure this is the right place to post this but i figure since i have hp tuners and using hp tuners scan tool to diagnose some of the problems id post here. it started this morning, my main battery ground was bad, had nothing, fixed the main ground, but being half awake first thing in the morning i left the key on... and everything picked up when i reattached main battery ground. not sure if that would cause an issue or not. now the engine rolls over, but no spark. the scanner reads rpms so im assuming the cps is good? i also took all the other grounds off, wire brushed and re installed, and still no spark, any other tests i can do? also checked all fuses, checked power at coils all is good
Last edited by 331camaro; 07-09-2016 at 03:28 PM.
#2
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U have power at the coils or at the plug in to the coils bracket on valve covers . Do u have power from the coil going out to the plug wires basically just asking where is the 12v ending on you
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The plug going to the coil 12v side has power, also last time i ran the scanner i did see the advance column rise as if the pcm is throwing timing at it trying to get it to run maybe theres a bad ground from the factory within the harness, afterall it is 16 yrs old
#5
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Coils need 3 things. 12v ignition (fused) on the 2 pink wires, Good ground on the 2 black wires, and then each of the 8 others going to the ECU.
If its still not firing, it could be a bad ECU ground.
If its still not firing, it could be a bad ECU ground.
#7
is it a stand alone harness with 4 or 8 fuses? I've had problems before when my battery went dead. after new battery installed it would do everything but crank. ended up pulling all fuses and reinserting them. Not sure why, but did the trick
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the ignition control signal from the pcm, is that a ground or 12v? i dont think im getting the signal from the pcm....checked the grounds, it does ring out from the ground pin to the block.
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checked for voltage at pcm on the low reference wire for the cam sensor, im not getting anything while cranking, would this prevent it from starting, ive read that the crank sensor should take over and start it