RPM's Stay's a bit high until fully stopped

[LibertyTC]

Sometimes the rpm's stay up around 900-1200 while braking at 10mph downward especially when cold, not as bad when hot.
Cleaned the throttle body and is better, but still what controls the rpm's and are they adjustable?
Feels like KJ is still being pushed forward while braking, (tried Neutral still up for a few seconds) should it not be lower?SHOCKED.gif

I have also noticed that while I am trying to warm it in Neutral, that I can loose 400+ RPM when compressor kicks in..I take it there is no auto adjustment to up the rpm's when compressor kicks in. hmmm....

 

[tjkj2002]

Sounds like at gummed up IAC(Idle Air Control),that is what controls your idle.

 

[LibertyTC]

ya ok so....Tips please on removal and cleaning...or replace?....
Just two screws and no spring? Must replace the o ring if removed? or can this unit be cleaned and stuck back in..best cleaner?

 

[tjkj2002]

Easier to just replace,there cheap and get OEM only.

 

[LibertyTC]

Thanks Tjkj will do.

 

[Prospect62]

I'm having the same problem...even after having my engine replaced. That bill must not have included a new IAC.

 

[kb0nly]

Yep sounds like a typical IAC problem....

 

[Porkchop]

Sure does been there done that

 

[LI02liberty]

If you clean it or replace it just make sure you clean the two ports that it sits in on the throtle body. Mine both had a ton of carbon in them.

 

[LibertyTC]

Thanks for that, I will just spray some carb cleaner on a small brush or something,will know what to do once the IAC is off. Thanks!

 

[Simpleman]

You might also check for a vacuum leak off of one of the hoses on the intake manifold.

 

[Porkchop]

Had Iac do this and showed good on the computer. Tryed one of well known quality and bing go worked.

 

[AlexKJ]

Sometimes the rpm's stay up around 900-1200 while braking at 10mph downward especially when cold, not as bad when hot.
Cleaned the throttle body and is better, but still what controls the rpm's and are they adjustable?
Feels like KJ is still being pushed forward while braking, (tried Neutral still up for a few seconds) should it not be lower?SHOCKED.gif

I have also noticed that while I am trying to warm it in Neutral, that I can loose 400+ RPM when compressor kicks in..I take it there is no auto adjustment to up the rpm's when compressor kicks in. hmmm....

Same problem here... I recently get the TB cleaned though...

Easier to just replace, there cheap and get OEM only.

eeerrr... Not an option for me... over here the Air Idle Speed Motor (P/N 53030840) costs USD 172.22... Better cleaning it up

 

[AlexKJ]

Yesterday I tried to clean the IAC

Yesterday I tried to clean the IAC. I disconnected the battery, pulled the plug from the IAC and took off 2 Torx screws. The result was a plastic black piece in my hands and something like a tab remanined in the throttle body.

I tried to turn the tab, but it wasn't budge... I was too afraid to do it harder nevertheless.

Then I proceed to spray contact cleaner on the plastic part and WD-40 on the tab... then I cleaned and reassemble...

Any comments?

 

[kb0nly]

Yesterday I tried to clean the IAC. I disconnected the battery, pulled the plug from the IAC and took off 2 Torx screws. The result was a plastic black piece in my hands and something like a tab remanined in the throttle body.

I tried to turn the tab, but it wasn't budge... I was too afraid to do it harder nevertheless.

Then I proceed to spray contact cleaner on the plastic part and WD-40 on the tab... then I cleaned and reassemble...

Any comments?

You sure you removed the IAC? The TPS, Throttle Position Sensor and IAC are on the drivers side of the throttle body. The IAC is the bottom or lower one.

From what your describing it sounds like you removed the TPS.

Here is what the IAC looks like, its like a plunger that goes into a bore.

 

[tjkj2002]

eeerrr... Not an option for me... over here the Air Idle Speed Motor (P/N 53030840) costs USD 172.22... Better cleaning it up

Well when the ports and the IAC itself get carboned up it puts alot of stress on the IAC motor,which can damage it and strip the gears a little.So just cleaning it may not(almost all the times from experience from cheap customers) fix anything.

 

[AlexKJ]

You sure you removed the IAC? The TPS, Throttle Position Sensor and IAC are on the drivers side of the throttle body. The IAC is the bottom or lower one.

From what your describing it sounds like you removed the TPS.

Here is what the IAC looks like, its like a plunger that goes into a bore.

Mmmm... maybe it was the TPS ... I'll check again later...

Something about the cleaning method?

 

[kb0nly]

I agree with tjkj... Cleaning it really isn't likely to fix it, its worth a shot for free, but you better plan on buying a replacement.

 

[LibertyTC]

Can anyone look to see when cold and you first start the kJ, what is the rpm reading?
Mine seems to be about 1000 in Neutral and takes a few minutes to get down to around 650rpm. Is this Normal?

 

[tjkj2002]

Can anyone look to see when cold and you first start the kJ, what is the rpm reading?
Mine seems to be about 1000 in Neutral and takes a few minutes to get down to around 650rpm. Is this Normal?

Normal