How would I go about testing my ignition module with a multi-meter? my ecm posted up soft code 43, my check ingine light would go on and off but only after sitting idle and getting fairly hot 220and started running like s@#t. I checked my knock sensor and it read 3.7k or close to that so i dont think its the k/s. I checked the conn. at the coil and the back of the distributor their ok. what else can I do? maybe check for a short in the wiring all the way to the ecm?
OH, Its a 91 GTA, small cap HEI,external coil.

 

Code 43... The ESC retard signal has been on for too long or the system has failed a functional check

Apparently its a real pain in the *** to find the source of.

Its a GMPP Vortec 330 with their horrible TBI intake bored to 2" and a 454/5.7 injectors.

Replaced knock sensor along with plugs, 02, coolent (nothing wrong with the knock sensor, my first mistake) and suddenly Code 43... checked the cheap GM pigtail connection...

Checked base timing at 0 degrees and when plugging the computer in it advances but jumps around rather eratically. With this code it'll toss back timing 20 degrees, right? Might be horrible ECM tuning...?

I'm going to put the OLD knock sensor back in... start from there.

Thanks

 

Replaced new sensor with old one. Fixed.

The saying is very very true... not broke don't fix.