I've been having major overheating troubles due to something going on when I turn my A/C on...but thats another issue.

Every time the temps go way up from the overheating my engine would detonate like a JOKE. All of sudden yesterday, the overheating happened again like it always has but I had absolutely no detonation. I pulled over and popped the hood and made sure it was actually hot as hell and it was, just like always. But no detonation.

Question is:

Can a PCM finally realize the problem and pull timing to stop the detonation?

 

The PCM doesn't "realize" a problem so to speak. It can pull timing based on IAT's and ECT. If the car was programed to reduce timing at a set IAT, then it will. It has some pulled from the factory already.

 

Is the ECT sensor located on the drivers side all the way in the front of the head with that brass look. Right above that spark plug, #1 plug, right?

 

Yes, that's the ECT sensor - PN 15326388, about $25 at the dealer.

 

Can you tell if its bad just by looking at it? After I take it out to look at it?

Does it show an SES code?