I have a supercharged 305 tpi had been running fine till now throwing a code 42 esc it keeps retarding the timing everytime i drive its bad.I had researched what could cause this problem so i replaced ecm, ignition control module, new spark plug wires one had a crack in it and still same probem any suggestions im lost with this one

did you check the knock sensor that;s part of that system

i didnt check it yet, i just got done talking to a mechanic and he had just said the same bout checking the knock sensor so thats next to check, thanks for the tip its driving me nuts at this point

I replaced the knock sensor and still same ploblem, im stumped any more ideas?

the memcal the thing that holds the computer chip. Contains the esc control. Did you replace it

there is an esc module next to the wiper motor with your other relays its flat and alil long if i recall that could be the culprit it bolts up to the bracket that your relays is on

maybe ya just got ahold of some bad gas....

ok looked in the shop manual check the timing by pass wire over by the blower motor could be unplugged ill get a pic of the problem tree later when i get my camara

if im correct with if the wire was unplugged you'd be locked at your base timeing...that would allow the timing to advance or retard...

yes i had replaced the computer not the chip. Let me know if anyone has any opinion on this one, i had bout the new accel ignition box with the coil built in i had mounted it pretty much on top of the blower box so the advance wire even tho plugged in it sat right on top of the coil could that have caused interferance for the timing advance? i just took the accelbox out and put my old msd blaster coil back in which is mounted not near the advance wire i have not gotten a chance to drive it but i started it, it started quicker and has more thottle response just sounds stronger now.So ill have to let you guys know tomorrow when i take it out.Yesterday i had a code 42 today when i had driven it before i changed the coil i had gotten a code 43

If the coil doesnt solve the problem ill try changing the esc module.Some mechanics are also telling me to replace the knock sensor again could be faulty i guess. Thanks for every ones suggestions hopefully it will run right soon

You can rule out the knock sensor by replacing it with a 100K resistor to ground.
Unplug the knock sensor connector at the engine and connected it to one side of the resistor. The other side of the resistor is connected to ground.

I have a resistor where I installed the correct wheather pack pin on one side and a ground terminal stud on the other to make it easier.

Just remember that with the resistor installed the ECM will not sense and knock and will not retard timing.

Most of the time these problems are at a connector or a broken/almost broken wire. That is where I always start. I ohm out all the wires that are associated with the code.

Thanks for the tip if it comes down to it ill try that out, as of today with taking the accel ignition box out and puttin my other msd coil back in seems to be good so far no engine light or loss of timing so when i get time ill take it out for the long haul and see how it is and if stays good. Thanks for everyones input and suggestions its a great help