So i was driving home tonight and i put my car in neutral while coasting down a hill and my idle slowly came down then quick jumped up and held there. When i put it back in drive it leveled out to normal and i kept driving. So i came to another hill and i left it in drive but let off the gas and coasted and it did the same thing but the RPMs didnt raise as high. Im completely confused

Thanks!

 

Anybody?

 

how high did the rpms rise when you were coasting and put it into neutral?

 

Also does the car run weird else then that?? IIRC thats not that abnormal if were saying it went up to like 2k rpms or so then dropped if you were costing down the highway.

 

on that question.

Sounds like the IACV is doing it's job, pending on how high the RPM's went.

 

Well my tack doesnt read properly but according to it, it went from 1500 while coasting in neutral up to about 2500 or so and held until placed in drive

 

the car also runs fine otherwise

 

Have you cleaned your idle return spring on your Throttlebody to ensure it isn't stiff or sticking?

 

Where might this spring be located on the throttle body?

 

I dont think there is a spring at all, but two cables going to the TB. one is the throttle and the other idk