I have a buddy that I am trying to help out. He has a 2003 Ford ranger 3.0 V6 AT. The truck will crank fine but whenever he gives it any gas to get up and go, it just bogs down, not allowing the tranny to change gears. It's almost like it has a rev limiter on it. Max speed on the highway is about 45-50 mph. We have tried all the obvious. He has changed the fuel filter, all new plugs and wires, and new coil. We also checked the compression on all cylinders and #4 and 5 cylinders are reading low. All others seem to be fine which leads us to believe there is a possible blown head gasket. Before we get into changing a head gasket we are going to try the maf sensor thing. I am not real confident that will fix it though. Any other ideas?

 

What do you mean by "fix the MAF thing?" Are you talking about cleaning it or replacing it? What is going on with fuel economy. I'm guessing it has dropped. Is the CEL lit? You probably should check for any trouble codes. How many miles are on the truck? You may have one or more oxygen sensors wearing out.

In short, do more diagnostic work before throwing more parts at the truck.