If anybody could help me with this I would greatly greatly appreciate this. I've got a 2002 Chevrolet Suburban lt with flex fuel system. I just recently moved from Alabama to Arizona about 400 miles away from Arizona the truck started spitting and sputtering and losing throttle response like it wasn't getting fuel. I can shut the truck off, restart it and immediately works perfectly fine. I have pulled engine codes and it gave me a code for the flex fuel sensor and the evap purge solenoid. I have replaced both and the truck still does the same thing it seems to be getting worse. I currently have an H pipe set up exhaust no catalytic converters and Flowmaster muffler so I know it's not back pressure coming from the exhaust. No sensor is showing to be faulty. At first start up the truck runs perfectly fine anywhere between 30 minutes to 2 hours it just depends on how it feels lll. after that it will start spitting sputtering backfiring until I pull over and shut it off. Upon starting it back it's perfectly fine. Also the fuel pump relay gets really hot I have replaced it multiple times as soon as I replace it is perfectly fine I'm really hoping this is not a fuel pump issue but I'm sure someone out there has had this issue before and I'm just looking for advice any help would be greatly appreciated thank you very much.

 

what were the codes? Have you checked fuel pressure or volume?

 

Codes were I believe p0402: flex fuel sensor. And po174: evap purge solenoid. Both replaced and no cel's currently. Planning on that tomorrow was just hoping someone ha ran into this before. I'm on week 3 and $850 into it and getting frustrated lol