Ok so i get my car put together 6.0 l92 heads, 233/239tsp cam, ls3 intake 90 mm tb, i got a tranny and yank 4000 conveter that was built and working with 600 miles on it in december and just got it put in. I put conveter in the pump and so on, put it in the car filled with fluid and so on. I start the car up ( car tune is way off won't idle above 500-600 rpm) needs tuned bad. But anyways i put it in reverse, it does nothing, i put it in netural it goes forward, i put it in drive forward, 3rd forward, and then 2-1 don't move at all. It is throwing codes like po785 , p1860, Po740, PO756 , so pretty much like shift silnoids a,b,and c. and so on and something like TCC circuit malfunction. The big plug is plugged in, i have taken it out and put it back in multiply times, i have checked the speed sensor, also not the shifter linkage either because i did it by hand, pump is working pumps 1/2 to 1 quart in 10 to 15 seconds. Could it for some reason be because the tune is so off and the car is barly running ? I don't think so i have talked to a tranny guy and he said it didn't matter if even the big plug was undone that the tranny still should go into reverse and forward and so on with the hydrolics? I have drained fluid looked at it no metal nothhing evertyhing was plugged in under the pan. Put fluid back in and still same thing. I have checked all fuses under hood and all are good none blown, cleared codes and still does it and comes back with codes. ANYONE got any info for me please !

 

stock pcm out of my 98 trans am.

came out of a automatic 99 camaro ls1 car

 

i have found out that it might have something to do with a low or no power getting to the plug is why its throwing all the codes. So yes i need to check out the harness from the tranny to the pcm and so on to see what the deal is , or a fuse. No its not the same tranny its a different one from before. Also reason reverse won't work is probably sense its a 4000 stall and i can't go above 600 rpm to make it turn. And won't go into 2-1 because its in limp mode and doesn't have the pressure to switch because of lost power. So i need to try and locate reason for loss of voltage and wondering where it might be at. Any help with from tranny electric plug to god knows where it goes and what to check lol ?

 

def sounds like computer or tuning problems. the computer pretty much tells the tranny what to do

 

so 2 nights ago i had the battery hooked to the charger because its low. Started running at 500-600 rpm no codes... Well when it threw these codes it was ideling 500-600 with no charger and low voltage on the meter only like 10ish . . . .. so thats telling me that right there is just not producing enough power with the low rpm to charge the altnator and battery therefor sending tranny into limp mode throwing 1 million codes !

 

10 volts is just to low make sure you have a good battery & altenator while the car is running you should have about 13 volts at the battery.If you still have codes check ingnition switch.

 

ya altnator probably doesn't charge to well at 500 rpm. and ya battery was at about half life needs put on a charger.

 

well car is running and ideling now higher. throwing the p1860 code which in turn throws all the other codes. I don't know what to do