I have a 5 speed and from time to time engine starts rev high at a stop with clutch in if I step on the brake its stops reving any ideas? I'm not moving clutch is pushed its wierd some it doesn't sometimes it does.

 

My ’98 2.5 had a similar problem when I got it. I found the vacuum hose to the EGR solenoid was cut in half causing a vacuum leak. Also there are some hard plastic vacuum lines that I had to replace. So I would start by looking for a vacuum leak.

 

If its not a vaccum leak clean the IAC valve, mine was dirty as hell and was causing me to idle between 1500 and 2000 rpm, cleaned it and got my idle down to 900-1100.

 

a bad pcv valve will cause a high idle and not throw a code.

 

When I first got my Ford Ranger 5 speed auto (I know you have the clutch, but same situational problem, possibly), I took it to the dealer because I was concerned about how high it revs up when sitting stopped, whether in neutral or park, and they told me it was so the engine could warm up (around 1,500 rpms), but it does it even when the temp gauge is in the normal range. To make matters worse, when I put my foot on the brake and shift to drive or reverse, a loud clunking sound is heard and the entire vehicle is jerked, as if you were to shift without using the brake (if the interlock wasn't in existence), or if you were to hit the gas while the shift was in process, that is what it feels like. I don't know if any of this helps

 

Weird mine does this too sometimes, any thing you did that helped? ps mine is a 96 2.3