Unexpected open loop

[razzer]

2015 Tahoe 5.3 in my Jeep and it drops into open loop long after reaching operating temp. What criteria can cause going into open loop? Or what limiters are set to get it to go into open loop?

[TCSS07]

Any dtc's? Without a tune file its a little hard to say but usually if the ecm randomly goes into open loop and comes back its doing a o2/cat test so under engine diag/exhaust - make sure the post o2 and catalyst tests are disabled.
my lsj would randomly do that when i removed my rear o2 sensor and the ecm was looking for a input and couldn't find it. Made the car acted all f*cked up but i dont have access to the o2 test like must other ecms do so i had to install it back and also the misfire counts would cause it for me as well so i disabled the misfire counts and issue solved

[razzer]

It ran pretty ok for just under a year since the install. What normally happens is ... after 5-7 miles the light goes on with a code of P420 and P430. Within the next 5-7 miles it jumps into open loop, I notice that trims are sitting on zero, and I can smell the richness. Today ..... I have a 26 mile drive to work. After about half the commute I stop for a coke and upon a restart it went right into open loop. Ran like crap of course. Continue to work. I drove it home later, playing and feathering the throttle to avoid stalling, and about 18-20 miles later it went back to closed loop and drivability cleared up fairly well. Same codes were still there when I got home ... so frustrating.

[5FDP]

If you aren't running the stock cats, you should probably disable those codes along with the cat test.

They may still show up as a permanent DTC for a while but that is okay. Set them to no error reported.