rlcole321

there is a temp blend door for each side, sounds like the driver side is not working or is stuck to heat. in a quiet place, with key on (door closed to keep dinger off) run the passenger side temp control from "LO to High temp and listen under the dash on the pass. side and see if you can hear the blend door moving, if you do then repeat the same thing on the driver side and see if you hear the door moving, if not then that's the issue, try it a few times might "Unstick"

could try lifting the truck up all 4 wheels, put in 4WD and listen, that way you can walk around the truck. then have somebody tap the brakes.

I think there was a big change in AFM control from 2018 to 2019, so look into that, may have to swap some parts around.

My two cents, I have a 2018 'Rado and my HP fuel pressure is a lot higher than that, in the 1,500 psi range and higher, may look into that. Have you told your GM tech about your low HP fuel range

Picture would be helpful, yes, you need a VERY stout air gun to get that crank bolt out and GOOD torque wrench to put on a new one (unles you use OE, then torque to yield). There's no gasket involved, just RTV, so be sure where it's coming from. Frt Cover is not easy to get off, sometimes it's better to pay a Pro!

Does any of the U codes come back when you clear them?, how long have you own the truck?, has the engine compartment possibly been pressure washed? You may want to pull the connectors one at a time off the ECM and check for possible corrosion.

well if it shifts ok manually then sound like a TCM issue, may need to "Reflash" a program to the TCM, if it shifts ok in manual mode then the hardware should be fine.

Check all connection at your battery junction box!

Ditto!

The code means an issue between the Baro data and the MAP data , I'd check for an air leak in the intake system, possibly giving false data from the MAF. I believe the ECM pulls baro data from the map sensor.

Yes back in the days, trans was "Warmed" up by the coolant. I was an auto tech for 20 years (back a while, OBDII had only been out a few years when I changed careers) and I always thought trans coolers were in the Rad. (so when I got my 2018 'Rado, I didn't understand why GM used a Trans tstat), I didn't think about it until I did a DOD delete on my truck and took it apart that the trans cooler was in the condenser, then the trans tstat made sense! So unless your a performance wild man, your trans need to warm up just like your engine, so running a trans tstat makes sense and I think 190 is too high.

What are the symptoms of TC failure? usually there's evidence in the pan before an issue with the TC. Now there's nothing wrong with changing out the TC or upgrading it but just wondering.

Quick Tip: if you suspect the starter, try "Tapping" it with a hammer or heavy metal object while someone turns the key (or if nobody is there you can bang it then try to start it), it will most likely start if it is the starter. sometime there's a "dead" spot in the armature windings and if the starter stops in that spot, it won't start, tapping it will "disturb" the armature and cause the starter to work.

If it is not a lifter/push rod/cam issue, another problem could be a leaking injector seal in then cylinder head, this is a direct injected motor, the injectors spray directly into the combustion chamber and could account for the lower compression.

try to find a right angle (90 degree) drill. Should give you enough room. And come out easy.

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I don't see any clear evidence of a head gasket failure, you may have Block or head crack issue (where did the coolant come from??), I would verify before doing all of that work and putting it all back together and the same thing happen, Or maybe start off with a used motor and go from there.

It's not the "Operation" software that causes the problem, it's the lifters that fail, even when you get the truck back from the dealer, it will still have the AFM/DOD lifters in it, just using a "Dongle" to disable it wont stop it from happening again. The only fix is do a DOD delete upgrade, which the dealer can't do under warr. Non DOD Cam and lifter replacement (as a minimum), and a tune. Learn how to use HPTuners.

Have you tried to shift it manually?, have you look at the fluid, is it burnt or dark colored?.

Speed Engineering

Well "John needs help", thats for sure, only thing I can say is "Dealership", I know most don't like it, but in your case, you HAVE to get the right programming done to start!

I think your right, they didn't change it or installed the wrong one, maybe there on back order (I had mine done a couple of years ago and had to wait because it was on back order), some info, your trans cooler is part of the AC condenser and not in the radiator (unless you have a heavy duty tow packages)

Yeah, first check should be battery and terminal connection, batt should have 12.3 to 12.5 volts, then check when running (after start up), should be at least 14 volts. Now if all that checks out, if or when it is a "no start", (if you have a battery charger) attach it to the battery, put on high and check battery voltage, if above 15.3~16 volts, then the batt is "Sulfated" and needs replacing. (sulfated is when sediments "Clog" the plate structure and keeps the charge from penetrating deep into the plates). Now if all that is good, then check the ground connections, it is a common problem, you can search YouTube and find a bunch of info on that. Normally a 2018 truck would have already "Expose" a grounding issue due to age, but it still could be be!

First, how long have you had the truck?, what is the milage?, does it have the factory 207 degree thermostat in it?

you'll need to pull the pan and check for Debrie.