i recently put a new distibuter, cap and rotor in my 89 gta 350 tpi, iset the timing at 6*the car ran ok and seemed fine but then the ses light came on code 42 and the car seemed to lose most of its power it would still run but shaky at idle and not enough accel, so i played with the timing some more i raised it to about 13 14* or so past the indicator marks the car feels good through low rpms has power accels ok and idles alright but when i stomped the pedal to the floor it sputters badly and backfires so something is still off, i set the timeng basically by trial and error and listening to how it was running, at 6* it would run fine but had no power once i advanced it it still runs ok and has some power back but still a loss at high rpms it seems the computer isnt advancing the timing maybe.... would that explain this problem 6* is just base timing if the computer doesnt advance it it would result in low power right?? and moving the base timing way high like 13*14* would make it run better because it isnt being advanced but still would not be completely right correct me if im wrong anywhere here ... is there a way to check the esc resistance voltage ect it seems as if the esc might be an issue not it doesnt seem to be advancing the timing on its own i need to get this fixed right once and for all. by the wayfuel pressure is good also new plugs wires injectors and computer for some background. and i did discon the brown and black esc wire while setting timing and cleared computer of all code numerouse times.

 

You should be able to monitor the voltage from teh 'C' terminal on the ESC module for changes. If I am correct, there should be a +5VDC signal present, and the signal will get pulled low (0V) when the ESC detects a detonation event and requests a spark retard from the ECM.

 

Thanks this is exactly what i was looking for.