96 burb stuck in limp mode

[Glasspack70]

Got the truck with a bad lower intake gasket. Had water in the oil. I pulled the heads installed new gaskets and bolts. flushed the motor. runs great. But I'm new to electronic trans and, I drove it with out the intake tube, because i had yet to clean the oil from it. and low and behold it wouldn't shift. So I did a fluid and filter change on the trans. no metal in the pan but the fluid was more brown than red.

Still no shift. Googled the prob and found out about limp mode(never heard of it before). hooked the code reader up P1864 tcc enable solenoid circuit malfunction and p1886 trans axle shift timing solenoid performance. I tested the A and B shift solenoids and they tested good. cleared the computer codes. not pulling any new codes and still stuck in limp mode. all fuses are good & triple checked to make sure everything is connected. Any ideas? guess i forgot to state that it is a 4l80e

[gmtech4]

it needs to diagd for the codes by a technician,there is to many things it can be and throwing parts at it does your pocket book no good at all,

 

sry

 

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