I have a 1996 Ford E350 7.5 L Gas RV. I was driving from Houston Tx to Baton Rouge La and the Rv bogged down on me on I10 after about 80-100 miles I sat on the side of the highway for about 30 minutes and continued to drive and it lasted about 30-40 miles before it did it again, it will be like this for the remainder of the trip length of time would vary and I saw no correlation with amount waiting and distance driven. What I did notice was the last time it happened there was a cold front storm that blew in and it dropped the temperature significantly my RV was able to make it to the RV park without a problem while driving in the storm. While I was driving I hooked up my OBD2 scanner and was monitoring the engine and noticed that when It would bog down my short fuel trims would spike up to 30-40 % and I would lose power pressing on the gas would make the power loss grater I had to lightly give it gas to keep driving without slowing down significantly and then it would only drive around 30-45 mph. Another thing to note is my e350 AC does not work causing the temps to get hot under the foot well and when the RV would bog down it was extremely hot down there. The only thing I've changed to try and correct the problem was the MAF sensor but that didn't work. a similar thing happened before on a trip to Georgia but I thought the changing of the MAF sensor fixed it when I drove that time it was in the winter so I am assuming it didn't happen anymore because it was cold. My engine temp/ coolant temp read normal. Any insight would be greatly appreciated. P.s I also did a complete tune-up when I bought it including a new air filter, spark plugs, spark plug wires, distributor cap, and fuel filter. RV has 42,000 miles