tbarn

Remove left valve cover. check for broken valve spring. If you are sure both on #5 are ok then reattach the coils so you can run it with the valve cover off. Loosen #5 intake and exhaust rockers slowly one at a time and see if the miss goes away. Sometimes a lifter will stick in the "up" position as if a solid lifter.

In theory, yea.

Last I knew it was not a serviceable part. Whole rack or nothing. Maybe things have changed. It would need programming or at least a setup procedure.

FYI it's BPP in GM speak. Only the sensor, ECM and 3 wires involved. Sounds to me like you have a wiring or terminal issue. There is a TSB regarding this exact issue. Whether they saw it or used it fully is anybodies guess.

Right side IP fuse box? Fuse F46DR?

Nope

Scan, scan, scan. You can't possibly know where to start without scanning it.

Evaporator.

Really? Show me a hundred trucks and I'll show you a hundred different settings.

No slamin' for me. Yuk.

OMG!!!!!! I've never seen this Rivan truck til now. Ugliest truck EVER!!!! Reminds me of the Tartan Prancer from the newer Vacation movie. Hideous. Or maybe something from Lost in Space.

So you can get rearended?

Easy solution. Take that pedal commander off and see if the problems continue. If the trouble continues make it's out before going to the dealer. Save yourself and the tech a lot of trouble.

Was a 0% alternative not offered? Usually it's xxx rebate or 0% for x amount of time.

Seems to me most of those are very expensive vehicles.