The truck has under gone some maintenance, we change spark plugs, oil, oil filter, we ran into the problem where it randomly wouldn't crank over. We suspected fuel pump, changed that out, started it up noticed the pulley system for ac had some barrings going bad.. we deleted the AC put a new pulley system on for belt... Truck started. Had a rough and very low idle.. 500 rpms.. we drove it seem to have no issue. Besides the low idle when we were stopped (red light, stop sign) such a low idle it would kill itself... Driving 65 on highway the rpms shot up died shot up and killed the truck.. The fuel pump still runs we have replaced the fuse for the fuel pump, honestly just running out of things it could be, need some help before I junk it. I know it's something so simple. It's never ran like this before.