LS4 open loop fault switching at idle from closed loop, back and forth

[Spawne32]

Just put my LS4 07 grand prix GXP back together, removed the DoD system, threw in a 214/220 .540/.535 115+2 LSA cam, headers and intake. Car has been running fantastic, been doing alot of tuning, disabling things in the tune file like DoD, cat overtemp, changing idle settings to get the cam running smoother, etc. I noticed over the past 2 days ive been tuning that i seem to have an issue where the fuel trims turn off for some reason, narrowed it down to it switching been closed loop and open loop consistently, but fuel system status is displaying "FAULT" when it switches, and its not giving me any DTC's (P0300 disabled among DoD codes). This seems to happen more consistently while at idle, it will go for a minute in closed loop, then it will fault, then go back to normal, and I cannot figure out for the life of me why. Posting up a scan of what its doing and the tune file.

[Spawne32]

couple notes as well, disabled the catalyst efficiency, and insufficient switching for B1S1 (single o2 sensor car) and no luck, and its also a brand new acdelco sensor installed with the headers.

[Spawne32]

figured out, apparently disabling the P0300 code does not prevent the system from setting a fault for it, increased the random misfire thresholds by 50% and dropped the total misfires from 120 down to 40 or so, and it went right into closed loop normal.

[MMGT1]

This just saved me a lot of headache! 5.3 with dod delete top done but the dod cam is still in there. Would not go CL until I did as done here, and it worked! Ordering a new cam from Texas Speed for it, but at least it's good until we get it.

[johnny_boii]

This just saved me a lot of headache! 5.3 with dod delete top done but the dod cam is still in there. Would not go CL until I did as done here, and it worked! Ordering a new cam from Texas Speed for it, but at least it's good until we get it.

What cam did you go with?

[MMGT1]

Low Lift Stage 3 from Texas Speed is the one I suggested. Its got a 550 lift that will be easy for a set of LS6 springs to handle. It's a stock gear and converter truck, so its as big as I would go unless changing the converter at min. Bore is so small though that cam will be a lot bigger in there than most would think.

[johnny_boii]

Low Lift Stage 3 from Texas Speed is the one I suggested. Its got a 550 lift that will be easy for a set of LS6 springs to handle. It's a stock gear and converter truck, so its as big as I would go unless changing the converter at min. Bore is so small though that cam will be a lot bigger in there than most would think.

Keep me updated on what it makes, I have a 5.3 that I took apart and I can't decide what cam I want to go with

[MMGT1]

Hit me up with a PM and I can probably help you decide on something that'll work for you. Cam is so dependant on supporting mods and intended use. I can help...