Ok...Already replaced fuel pump, cam sensor, crank sensor, tps sensor, and ECM. Unplugged O2 sensor and nothing has changed the loss of power after a few miles. Lost and don't know what to do. Starting to suspect exhaust.

 

How's your cat? Has it been replaced, or hollowed out? May be getting hot, and choking off the exhaust. Could try physically removing the pre-cat O2 sensor, and see if things change.

 

Ok, so I have hollowed out the Cat an put a full tune up on truck and there is still no change. truck will drive fine till it is warm and then loses all power and starts sputtering and backfiring. Tried hooking up a scanner to read live info but scanner cannot communicate with truck for some reason.

 

So the list so far stands at...fuel pump, cam sensor, crank sensor, computer, tps sensor, plugs, wires, cap, rotor, and hollowed out the cat. Help please. I cannot keep throwing money at this truck.

 

Have you tried running it with the O2 sensor disconnected?

Losing comms when it starts running bad isn't really a good sign..... Will your scanner talk to it otherwise? If so.... where did you get your PCM from?

 

I have tried with o2 disconnected and there was no change. Used a snap on scanner and it communicated with the truck. All sensor show good specs. Everything is apparently working like it should. When it acts up I get a random misfire code. But that's it. By all rights truck should be running perfect.

 

See what engine coolant temp, intake air temp, look like when it is acting up. Can you do data logging with your scanner?

 

All temps are normal. All readings are normal except it shows truck running a little lean. but o2 is cycling trying to fix problem.

 

Is that what the scanner says? Sensor for PCM is separate for sensor for the gauge.

Something is getting hot, and failing. But, you have already replaced all the usual culprits.....

 

Its what the scanner says.