2.5L ('98-'01) 2.5 manual Rpm takes ages to drop when shifing in 1st and 2nd

[MadLadDon_23]

I have a 1999 ranger with the 2.5l 8 spark plug motor paired to a 2WD 5 speed manual and ive been having this issue since I bought it about 5 months ago where when I am taking off in 1st gear I usually let the rpm get to about 3500, 4000, and I have to wait a solid 4 seconds for the rpm to go down enough for a smooth sift point. Is this because of a bad IAC or something else. I have verified there are no vacuume leaks as I have resealed the whole topend of the motor. I will also mention that someone before me removed both front wheel speed sensors for the abs system and I haven't put them back yet.

 

[franklin2]

Wheel speed sensors may help it, not sure how it's programmed. I will say all newer vehicles do this somewhat, revving the engine up and then having the throttle slam shut creates a lot of emissions. They bring it down slowly, but probably not as slowly as you are describing.