So background story:
Got this Ram for $800, has a 5.9L, Gas, Single Cab, Short Bed....When I first got it, it idled at like 2k RPM, the dude I got it from got it down to about 800 RPM by turning something, forget exactly what it was.

(This is besides the point, but the dude had like 10W-30 in there..and lawn mower gas, so that might have had something to do with it.)

But since then I fixed a plenum leak and an exhaust manifold leak, got headers. Just started it up for the first time the other day, and it was at about 700-800 for the first ten seconds, then shoots upto about 1500 RPM.
It still has a squeak from the belt and a stud stuck inside of the head still. But it had a horrible tick, which has since gone away! So thank you to everybody that gave me some advice on that, helped a ton!

I'll post before and after videos shortly.

So next question is, why does it idle so high? It sits at about 750 RPM when I first start it for about ten seconds, then jumps to 1500 for a little bit, then comes back down a little bit, I'm not too sure as I haven't ran it too long.
Thanks in advance!
-Jake

 

Iac stuck, Vac leak somewhere?
Possibly the throttle stop witch is set at the factory and not supposed to be adjusted. ??? The iac will allow enough air in to adjust the idle.