So I recently change my oil pump because it went out and I wasn't getting oil through my engine ect ect. Well after fixing that and running it for awhile and getting the oil though everything it started idling extremely high around 5-6000 rpm. I got it off and waited a minute cut it back on and it immediately jumps to 5-6000 rpms and just stays there. I've left it running for minute to see if it would go down, it didn't. Put it drive to see if it jump down some, it didn't just constantly stays extremely high rpms. Haven't touched it in a few days due work but I really need to get this stupid truck running right any tips in the right direction would be helpful

 

I'm not familiar with the 4.7, but did you have to unplug any sensors to do this? If so I would double check all sensors and connections before continuing

 

5,000 RPM is really high, so don't run it like that.

A vacuum leak will cause a high idle. With the hood open, have someone start the truck. Listen for a persistent hissing sound or sucking sound. If you hear that, then look for a hose that is broken or disconnected. I would start at the intake manifold and work outward. The hoses for the PCV get so hard they will feel like plastic. Replace them if they are like that.

If you don't think you hear the sound, have your assistant turn the engine off and listen for that same sucking or hissing sounds as the engine dies.

Be aware that the throttle body being closed at idle will normally make a small hiss due to air passing through the small opening or the bypass.

Could be idle air bypass broken I guess. Also note that the PCMs are near 100% failure on Gen 1s, so every D will need a new one eventually. Sometimes you can test the PCM by putting a 1 gallon ziplock bag full of ice as close to the PCM as possible (might need to remove bolts) and then see if the situation improves.