ESC diagnostic

[Joe Boucher]

I don't think my ESC module is working.  I was experiencing knocking, so I retarded my timing.  Then I thought, that ain't the way this is supposed to work.  So, I dug in the factory manual, and
found some diagnostics.

I thought the system worked by grounding a wire from the ESC module through the knock sensor.  The one in the Suburban was new when I installed the engine.  The diagnostics said to disconnect
the knock sensor and hook that wire "momentarily" to a 12 volt source while watching the timing mark.  Well, I tried both ways, 12 volt and grounding,  and didn't notice any difference in the
timing.

There was voltage at the ECS module, so it is powered.

I forgot to hook the knock sensor up and the next day the check engine light came on.  I rehooked the wire up and started the engine and the light was out.  I was rushed and didn't use the ALDL
to look for trouble codes.  I'm assuming the ECM somehow figured out the wire was disconnected, but how if the module isn't working?

Any suggestions?

Thanks,

Joe (Looking for fly turds) Boucher
'70 RS/SS Camaro  '81 TBI Suburban