got a retune truck runs like a bat out of hell .now here the problem.cold start up truck will not drop in to passing gears and will die within 1/8 mile at first stop sign from my house.it start up cut right back off(run for about 2seconds.if I leave ignition on and unplug ignition relay under hood and wait 30 second it start back up run fine .but still no passing gears.but once truck get around 18o degrees both problem got away.no codes use to throw code 121 and1635 but I replaces throttle position both code gone now .but still no passing gear trans mission changes fine .like I said 50$on stand by

 

So it's just not down shifting when you come to a stop?

 

it down shift fine ,but will not downshift under acceleration stays in over drive

 

Sounds like trans shift settings...possibly converter lockup also

 

that would cause it to shut off?and not start back

 

If the converter is staying locked up, yea it would cause the engine to stall.... But I don't know what was changed in your tune. Need to look mainly at your shift settings... Then at your shift solenoids

 

Get adjustement in tune


Ok do ya need the PayPal addy yet

 

What trans u running? What brand throttle bodie? does is shift manually if u was to downshift to 3rd or 2nd?

 

4l80 e,stockthrottle body.shift manual fine. wait on truck to cool down .I may have found the problem .the fuse box under hood the ignition relay .the ground wire pin was push out from bottom side .will post back if this fix it

 

fix the cutting off part .but still no passing gear .it randomly go into passing gear after truck get 180 degress plus. could tcc switch cause this problem any one