2007 Chevy Avalanche cyl #3 misfire, new almost everything

Hey everyone. Have a little bit of a head scratcher here. Here are some quick details on the truck and whats going on. Hopefully you guys can enlighten me a little.

2007 Avalanche LTZ 169k:

Recently did the AFM delete because of a collapsed lifter (2,200 miles ago) here is what is new / changed:

Fully Rebuilt heads (seals, springs, retainers, valve job)
New GM lifters
New GM plugs
New GM wires
New complete GM gasket kit
New GM non AFM Cam
New GM oil pump
New NON-AFM valley cover
New pushrods
New timing set
New air filter
Reprogrammed ECU

Car drove perfect for over 2,000 miles after doing all this work and now this is happening.

What is happening:
Service stabilitrak and traction control light comes on then goes away and the CEL stays on. When you shut the truck off and read it with a scanner it comes up with CYL3 misfire.

What I have done so far:
Swapped coil pack from 3 to 1: Cyl 3 misfire still
Swapped plugs and wire from 3 to 1: Cyl 3 misfire Still
Swapped injectors from 3 to 1: Cyl 3 misfire still
Compression check on cyl 3: 135psi compression within 3 cranks. manual requires over 100 for 7 crank

On post 1 now

The code you are getting will help, coils on the 07 up have been known to crack and short out. It seems to me you are on the right track.

Updated first post to keep a running log organized

updated 1st post

could be cracked plug insulator.... or bad wire...

Updated first post. Could really use some insight. I'm kinda running in circles here. Short of getting new injectors and compression test I have no clue what else to do.

You seem to have been assuming that an injector is either dead or working consistently.  I'd definitely try swapping injectors around.  After that I'd suspect a wiring issue.  Did you notice any difference in the plugs when you swapped them?  Have tried running a fuel additive to help with a possibly sticking injector?  If wiring it could be the wiring to either the injector or coil.

Are you checking for any new CODES when light comes on?

you should everytime.

ygmn said:

Are you checking for any new CODES when light comes on?

you should everytime.

Click to expand...

Yup every time its the same code. Cyl 3 misfire. Its usually either 1 or 2 counts but thats the only light and code I get.

enoniam said:

You seem to have been assuming that an injector is either dead or working consistently.  I'd definitely try swapping injectors around.  After that I'd suspect a wiring issue.  Did you notice any difference in the plugs when you swapped them?  Have tried running a fuel additive to help with a possibly sticking injector?  If wiring it could be the wiring to either the injector or coil.

Click to expand...

I actually just swapped around the injectors on saturday. Swapped Cyl 3 with cyl 1. Drove it for about 40 miles so far and no light has come on. Idle still feels not right but no codes or anything yet. Noticed the idle will randomly jump wile in gear from abut 500-700. Not sure if its related but just a simple observation. I checked for vacuum leaks by almost soaking the entire engine in a can of carb clean and didnt so much as flinch wile I did it. Checked the intake for any cracks and leaks also.

Well did a compression check and checked out. Hit about 135 within 3 cranks. Service manual says crank 7 times and should be over 100psi. It was climbing pretty quick so ruled that out instantly. Going to do a Coolant pressure test and see if anything drips out with a bore scope. Starting to think potential ECU or Wiring issue 

So I was able to pull a freeze frame today and saw a couple things odd. 1 freeze frame our of 3 said OL-FAULT. The other 2 freeze frames were fine. Another thing I noticed was the TPS is reading around 23-26% even when I am idling at around 650Rpm and 160-180 degrees. Is this normal?