I'm at my wits end with this truck. I have a '99 5.2 and it's giving me a very hard time. It acts like it's going to die going down the road. At first it was over 65 before it started doing that then over 55, now at any given speed. I've replaced the coil, and checked all plugs for proper gap and still no improvement. I used a ELM327 OBDII Scanner and no codes. So I'm at a total loss. At first I thought maybe fuel pump replaced that and still no improvement. Then cut off the Catalytic converter and it's clear and good so welded it back on. Checked all fuel injectors and they all sound the same. So I know it can't be a fuel delivery problem even though it acts as one. What are my other options that isn't going to cost me an arm and leg by going through the expensive process of elimination with spending tons of money on all the sensors.