Okay we did the scanner again just awhile ago, At 600rpms in drive we are getting 3degrees of knock retard, stalling up it goes up to 5 degrees of knock retard, we disconnect the knock sensor same thing, We pull the computer out of the car and my buddy holds it in his hands to keep the exhaust vibrations off of it thinking maybe it was the knock module, well no same thing, What the hell is causing all this knock in gear not moving? Also when you floor it, it goes to 12degrees of knock retard, What the hell? I have true duals and the exhaust dumped at the rearend, no egr, no smog, I have run out of things to think of, I thought I might need the lt4 knock module but since the computer was out of the car with him holding it I still got the same thing, Any help would help me out alot, I am about to just sell it.

 

Start with the obvious. Are you using at least a premium grade (93 octane) fuel? Don't discount the fact that the KM itself could be bad. Have you removed the crank pulley lately? Some are balanced with a small amount of weights and have to be reinstalled in the same position they came off in. Or maybe your car just has a mechanical problem that is causing it to detonate? Hopefully not that, but???

 

93 always, No mechanical problem when it was in the 94 z28, went straight from the 94 to this 96 only thing changed was the knock sensor since 94 is diffrent than 96, motor ran great in the 94, Nothing has been taken off the engine except for what I listed, I got the 96 with a blown engine so I dont have a clue of how it ran with the 96 engine,

 

Also I believe it is false knock, Cause my ls1 truck has had knock before and I could hear it in the engine, This is sound as perfect.Also I swaped knock modules with an extra i had and didnt fix the problem. So only thing I can think of is the pcm.

 

The PCM has no internal way of sensing knock. It can only get it's signal from the KS. So any mounting issues with the PCM itself doesn't matter. I would suspect a broken signal wire between the KS and the PCM. When the PCM looses it's KS signal, as in a broken wire, it pulls timing until the problem is fixed. However, it would throw a code for it. So 2 questions:

Did it have any DTC's and did you ohm out the blue wire from the KS to the blue PCM connector, pin 22? Careful, there are 2 blue wires on that PCM connector.

While you're there, check the blue wire for 5 volts and measure the resistance of the KS to ground. 3300-4500 ohms. If all that checks out, use some resistors from the blue wire to ground with a total resistance in the same range 3300-4500. If it still shows knock then AND you know the blue wire connection is good at the PCM. Then the PCM input channel is defective.

 

Cool, I will try that today. Thanks