Ok...got a hundred pics of this motor, let me know when you find it!

 

Here's some more...

 

These people might be able to help you with what it was used for on your truck.

| pi | wiring-connectors | gm | pigtails | 2-cavity | female | ACDelco TechConnect

 

Looks like it might be the knock sensor looking at all of those conectors Its down by the distributor where it goes thru the intake Thats why i probably why i couldnt see it in all the pics. Ill have to look later not there but i hope that is it Thanks for all those pics i was staring at those like crazy ill let you know if thats what it is.

 

How did you get your engine THIS clean??? It's practically sparkling!

As for your plug... I thought it was the AC plug, but that's ruled out I suppose.

 

*Moved to lightning and electrical*

hopefully we will find an answer to this there.

 

It all started when my son blew a lim gasket. So I thought I would take it down to the heads and play with it on the rebuild, cleaned and painted everything.

 

Finally found it. havent been able to get out to look at it again until today. it was the temp sesor that Bowtie2500 mentioned it was down below on the right hand side of the motor But dang that was a pain to find. Runs great again

Thank you guys for all your help and all the pictures.

 

Alot of great post on here helped me out with my new to me blazer. Glad I was able to help someone else out.