Truck stumbles then dies in reverse

Hello so for a short summary of what has happened that can help. Recent trip Vegas truck began stumbling then died towed to shop was told pump was bad which I knew cause I took off the fuel line when it happened and was dry. Replaced pump drove home from Vegas all good. Had a po172 code replaced air intake since it had a tear in the process I guess my throttle sensor clip one of the 4 wires got torn and I had to replace and re-wire a new clip. Did so and now I have no codes but recently when starting the truck I go to put it in reverse and it stumbles low rpm and if not given throttle will die. Recent events also I’m noticing is my Coolant temp sensor on my ultra gauge the temp tend to jump 15 degrees randomly I'm assuming that may be going bad. Any advice or have any feedback would be great!

 

# 1 Guess Something in the transmission harness drawing the system voltage down that causes the ECM to glitch .

Only happens in reverse never going from Park to drive?

Every start of your Truck is always in reverse??

This happens all the time no matter the Operating temperature of the engine?

Your stating of the Coolant temperature sender issues gives me my second guess.

# 2 Guess The ECM seeing a rapid change in engine temperature that is from a false signal reduces the engine rpm on a still cold engine causing the stumble. Allowing in more Air raises the rpm

Good Luck!

 

Happens mainly at first start up and only in reverse pretty much

 

Well I was replacing my engine temp sensor on the back of the motor and my ground wire wasn’t connected anymore from the firewall to the motor so I fixed it and I think my issue wasn’t the temp sensor like I thought but simply a broken ground…