Hey guys I'm have a real problem just did a cam swap and got a tune from black bear in my 99 1500 wen I put it to the floor it screams til I hit about 80 then the rpms just drop to about 1200 and it slows right down and I'm right to the floor it's like it's not holdings shifts long enought I just put bigger throttle body on it and I've Ben told that I might need a aftermarket MAF any ideas on what could be wrong

 

Did you get a mail order tune or a data log? If you got a data log tune, get a recording for Justin to look over.

 

Mail order and its throwing a few DCTs to there PO123 and P1121

 

your truck is doing that because your pcm and tps sensor are disagreeing about where the throttle is. unplug the tps and your 80mph pull again

 

okay thank you man now do I plug it back in after a wile or just leave it

 

Put the stock TB back on and re test it.

 

I unplugged my TPS sensor and It was bad the thing would Bareley brake 50 it was complet dog and the 85 mm throttle body is tuned in for the truck it won't bother anything to swap em out

 

did you unplug the upper or lower sensor? you could try a tps reset. unplug turn key on for 30 seconds then turn truck off and plug it back in.

 

Lower sensor and I will give it a try

 

do you have access to a obd2 scanner to read live data? curious to see if your pcm shows the tb opening and closing.