I have a 98 K1500 5.7L and when I accelerate under a load it spits and sputters. It threw a code for an oxygen sensor so I replaced that and now its throwing a Throttle Position Sensor code. I have checked the timing, replaced the fuel filter and MAF, and checked all the plug wires. Could the TPS cause it to do what its doing by possibly messing with the air to fuel ratio? I'm going to replace the TPS but if that doesn't fix it what else could it be? I appreciate the help and advice.

 

sounds like a spark issue I would power brake (load) the engine at ur missing rpm and watch for spark arcing