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

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

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

Swapped the crank sensor for the hell of it, still no spark, assumed that would be the outcome, must be a ground?

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.

I tried a spare pcm i had too, i have power on the pink wire at the coil and i read 0 ohms from black wire to the block ill check atound some more tonight

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

4 fuse set up, Tried that too hoping for poor connection, but there is 12v at coil. Havent had time to work on it hope to have free time this weekend

I had power to the coil itself, my problem was the fuel pump wasn't coming on. Then after a bit, it came back. Had that issue twice, both times was after battery change

There should be two grounds at the back of each head. Those are directly for the coils.

Andrew

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.

do i need a cam sensor reading while cranking i noticed i dont have one, changed the sensor still nothing

it's
 

ground.

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