lately when coasting to a stop in neutral my idle will climb up to about 2100 rpm and just hover there for a bit then will finally drop down to 1000rpm after i've sat stopped for a few seconds

what could be some culprits of this?
intake leak....?

 

anybody?

 

this has happened to me also, but very few times.
i don't know what causes it either..

 

Momentum?

 

ummm no
it drops down to normal idle of 1000 or so then climbs back up out of nowhere, not from momentum

 

Ah. I thought you were talking as if you threw it into neutral from a roll. My car will creep up a few hundred rpms when I do that. I guess from the instant load being taken off of the engine. Sounds like a strange problem though, maybe a problem with extra fuel in the cylinders?

 

well also when in gear the car will pull itself along at about a constant 2000rpm instead of decelerating
i can stay in gear and be on a street doing 30mph, giving it no gas but it will stay at about 2000rpm instead of slowly shaving off speed like it normally should...

 

Which leans toward a problem with your TPS

 

TTT
TPS is on the list, anything else i should be checking?

 

The PCM has tables for iac stepdown which is designed to keep vacuum to the engine while your moving for brakes. When your stopped do the rpms come down quicker?

 

Clean out your IAC, it is supposed to let a little more air in the engine while idling or when you let off the throttle.

 

it takes a few seconds after coming to a complete stop for the rpms to drop to normal idle speed (i mean drop from 2100rpm or so not the normal 1200rpm it use to be)

i have noticed that when slowing down, if i keep it in gear and let the motor slow its self down too like 1100rpms or so that it wont do what i've been describing in the previous posts, it acts normally
or if it starts to do the high idle deal that i can put it in gear and it will pull the revs back down once a load is put back on the motor...

thanks

 

I had a very simluar problem. I changed the fuel filter and cleaned the throtle body and IAC. All good now.

Asim

 

what are you guys using to clean out everything involved with the throttlebody?

 

Throttle body cleaner or good ole carb cleaner, just make sure you don't get it too much on the electrical parts. Oh and don't get it in your left eye, ask me how I know