car pings when accelerating, its not the gas, had the top end cleaned out did not help. timming is ok . now what

 

Knock sensors? But wouldn't a failure there result in a code? What ambient air temp./humidity were you operating in? And what was the car's operating temp. for oil and coolant?

 

no codes and the oil is about 212 and coolant is 198

 

I had a pinging problem with my 02. Not showing any codes. Dealer replaced knock sensor under warranty. Problem fixed.

 

Red Vette, that may be the best clue: you have knock sensor problems and no codes.

 

Can you test your knock sensors in the car?

 

I don't know nothing about the LS knock sensors. Here's how it works in BOSCH systems: knock sensor puts out a signal, recognizable to the computer, when the engine is vibrating with "characteristic frequencies" of 5-10 kHz. This is the "alarm signal". When the engine is not knocking, the sensor puts out "OK" signal. It's possible that the sensor is stuck putting out "OK".

To test it, you can plug the oscilloscope into the knock sensor, make the car knock and compare the signal against what it is supposed to be. Check it at both ends sensor and computer. It could be just faulty wiring, although the computer usually catches this. If the signal is wrong (the sucker puts the same signal regardless of the knock) - replace the sensor.

The computer changes the mixture and the ignition dwell when it sences knocking. I don't have access to the LS1 info, but one could use a dwell meter to see if the timing is properly retarded. You could also plug the oscilloscope in your injectors if the mixture is getting enriched.

Or, you could be a "sloppy joe mechanic" and simply replace the freaking sensor. Assuming you checked the wiring first, there is a darn good chance it'll fix it. It's probably cheaper and easier than figuring out what is wrong with the sesor "by the book".

 

Thanks for the info.