High Idle in Park & Neutral

'02 3.4L 5VZFE; automatic.

Even after the engine's warmed up, I'm sitting at 1500-1900 RPM in P and N. Immediately drops to 8-900 in D or R. Brand new air filter, just cleaned MAF & throttle body, then ran a can of SeaFoam.

Next step? IAC? Cam sensor? Coolant sensor?

 

Next thing i would try is clean the iac, you may need to have a new gasket for it though. Id replace it anyway.

 

Is your MIL on ??

What code are you getting ??

If you have a idle condition the ECM sees as not normal the light should trip.

Air leak in the air intake system??

 

My buddy had the same issue and did everything you did including the tp sensor. Nothing worked. I told him to disconnect his battery and after 15min he started it and it idled like normal.

 

I'll give it a go.

No check light, but I'll run it and see if any codes are present that aren't tripping it.

 

Been having the same problem, hopefully changing the iac will fix it.

 

You guys having any luck tracking this high idle issue? I've been chasing this problem for almost a year. Have tried many things: new TPS, MAF, IAC, coolent temp sensor, ICM (ignitor), and even put in a used ECM. Air intake and TB are all good, no air leaks, good gaskets, good vac lines, no codes, etc. Throttle cable adjusted. Sometimes idle is as high as 1700, sometimes normal. Usually high during first drive of the day but as soon as I shut down for a few minutes, and restart it will be normal for a while. I have a Scangauge and I have observed that when I am having the high idle, at the same time I will have poor mpg's upon deceleration. When the idle is normal, I will have high mpg's upon decel. Driving me nuts!

 

Did you fix this???

 

Anyone fix this? my exact problem just bought the truck. idles fine until its hot, works fine in drive, but park/neutral idles over 2k. Noticed it has a brand new MAF so someone has tried to fix this recently....Ive clean an IAC before but just trying to save $ and time if someone has come up with a exact solution.

 

I adjusted my Throttle position sensor and fixed my high idle!!!!!

 

I cleaned my throttle body and IAC and that fixed my idle. Wouldn’t have though so since it ran fine sometimes and other times didn’t but golden now!

 

the throttle bodies will wear the bushings and thrust washer out. The shaft that the throttle plate is attached to will slide slightly and hand open just enough for a high idle, next time it closes it sits like it should. push on the bell crank and see if you can slide the shaft. There are a few post about different "fixes".

 

I've heard of this issue as well... I had a high idle after cleaning my throttle body, took off the IAC and cleaned it and it idles perfect now.

 

https://youtu.be/x2YNC_CMbC0
this worked on my 2006 Tacoma, after replacing the valve cover gaskets and cleaning the Throttle body my truck was idling at 1500 rpm in Park and Neutral. after i reset throttle sensor idle was back to around 800 rpm in Park and Neutral.

 

Welcome aboard new member