hello, i have a 92 fj80 with a big block in it and a 4l80e tranny behind it but i can't get the tranny to shift right with the gm computer. it is all out of a 98 suburban. it runs in the limp mode and does not lock up the torque converter. any ideas would be helpful.the engine runs fine

 

Welcome to the forum! You can put a location down on you BIO, or in a sig file, cause there aren't too many stalkers here.

Did it ever run OK, or has it been this way since the install? Do you have the VSS hooked up? Are there any codes on the computer? (does it have the factory style ALDL?) What wire harness did you use?

 

it has never run right since the install , when scanned i get 2 o2 senser errors and a egr pintle position error but not all of the scanning plug is hooked up. the vss wire is not hooked into the computer it comes up to the harness and stops, i don't know where it goes on the gm computer, and chevy does not want to help, the tranns shops here in south dakota want to hook up everything like it was on the suburban, but that would take days to figure all out. the harness came from a guy that builds harnesses for conversions.

 

VSS connects to plug C1 on the computer, Light Green/black wire to pin 29, Purple/White wire to pin 30. The VSS wires connect to nothing else, just directly to the computer. The O2 sensors......do you have 4 on your rig? the K2500 Burb has 2 cats, 1 O2 sensor before and after each cat. I have seen in Summit catalog an O2 sensor simulator to replace the 2 after each cat (they just test the efficiency of the cats). The 2 before the cats are needed to trim the fuel mixture.

I can mail you wire diagrams of the Burb, to maybe help you hook it up. Was it a 98 K2500 with 7.4L? My scanner is having "issues" right now. PM me your address and I can mail you the 4 sheets.