false knock?
 

i have searched and tried all the tricks is it real knock? i start the car and it runs perfect for ten minutes then the knock comes. then it will go away for awhile then retutrn. tried running 100 octane but it still comes and goes. i tried tapping the block to see if the sensor works and it shows knock when i tap it then goes away when i stop tapping. could the sensor it's self be bad if it knocks when i tap. i have the lt-4 km could that be the prob?

Any help would sure be appericiated, i'm about ready to give up on this chevy and go to the darkside!

Re: false knock?
 

Have you considered the possibility that the solid motor mounts in your signature are contributing to the problem? The sensor is right next to the nount. Possibly you have a loose bolt, or the tube of the motor mount rattles on the through bolt when the engine torques under load?

Re: false knock?
 

pretty interesting. i will check the torque on the bolts. but if that was the problem why would it come and go?

Re: false knock?
 

I installed an lt4km and it greatly reduced my high RPM WOT knock retard. THe only time I really see it now is if I am spinning the wheels by accident or shifting hard. I have 1LE tranny mount which I suspect may have contributed to it. Had 11 degrees over 5000 RPMs before LT4KM, did a 1-2 run last night with 0 degrees and I could tell a difference in the smoothness as it revved. Good luck, 10 minute install and it can't hurt so go for it :D

Re: false knock?
 

You should never run all 3 mounts solid. The flex has no where to go. Expect a broken trans case when the power hits hard, it's the weakest link.

Ignore this if one mount is fluid (flexible).

I agree with Injuneer, my worn out old heap seems to retard from bumps in the road (rattleing suspension). You're surely picking up every noise and putting it right into the sensor with the solid mounts.

Otherwise you could read the plugs and if it's not real knock desensitize the knock sensor.