Idle Air Control Valve Gasket

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There is no idle air control valve. The electric throttle does this job and made the IAC obsolete.

On my 2014 w/ 343K miles, I have the idle dropping down to 400 rpm w/ occasional stalling. No CEL comes on, but I have not checked for codes.

I was going off this video:

How To Fix 4Runner Idle/Stalling Issues (IAC Valve) - YouTube

He points to a 5th gen that he says he had similar issues with low idle, but he’s working on a 4th gen.
 
Upon further run testing, the low idle does not happen until the engine is fully warmed up. It will then cycle to slightly below 500, then back to 500 to 600.
 
On my 2014 w/ 343K miles, I have the idle dropping down to 400 rpm w/ occasional stalling. No CEL comes on, but I have not checked for codes.

I was going off this video:

How To Fix 4Runner Idle/Stalling Issues (IAC Valve) - YouTube

He points to a 5th gen that he says he had similar issues with low idle, but he’s working on a 4th gen.

Just an FYI, the T4R he's working on in the video is a 3rd Gen, which was the last T4R generation that had a IAC valve.
 
No, it was snowing. This is December in Montana.

https://www.youtube.com/watch?feature=shared&v=5Yi3zPl_msE

A few things I would check:
Air filter clogged(my other cars airbox fill with leaves and car ran like crap)
Dirty TB
Dirty MAF
leak in PCV hose

It runs fine at startup because until it warms up it runs in open loop based off preset fuel/air calculations and is not using system readings. I am thinking MAF is dirty or air filter is clogged.
 
Is the air conditioner on when this happens?

A few things I would check:
Air filter clogged(my other cars airbox fill with leaves and car ran like crap)
Dirty TB
Dirty MAF
leak in PCV hose

It runs fine at startup because until it warms up it runs in open loop based off preset fuel/air calculations and is not using system readings. I am thinking MAF is dirty or air filter is clogged.

I went and checked the air filter. It was clean but seemed damp. My suspicion is from coolant as this vehicle had just suffered a seized fan clutch with the fan disintegrating and puncturing the radiator, sending coolant everywhere. Toyota dealer did the repair work, but I don’t trust them. I will also clean the MAF.
 
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I went and checked the air filter. It was clean but seemed damp. My suspicion is from coolant as this vehicle had just suffered a seized fan clutch with the fan disintegrating and punturing the radiator, sending coolant everywhere. Toyota dealer did the repair work, but I don’t trust them. I will also clean the MAF.

Yea I would guess the MAF is compromised by coolant since it will not evaporate. I would change the air filter and clean the maf thoroughly especially if you think its coolant. I would also try and wipe out all the intake tubes and clean the TB since the coolant will cause a coating that will not evaporate on all those surfaces.
 
Yea I would guess the MAF is compromised by coolant since it will not evaporate. I would change the air filter and clean the maf thoroughly especially if you think its coolant. I would also try and wipe out all the intake tubes and clean the TB since the coolant will cause a coating that will not evaporate on all those surfaces.

Closer look at air filter and no coolant contamination and it is dry. Cleaned the MAF, but it was sparkling clean when it came out. Test drive and still had low idle and a stall after warming up. Next I will clean the throttle body.

At the 4:00 minute mark of this video, he describes how the throttle body continually adjusts the butterfly valve opening to compensate for carbon and debris build up to maintain the 16% opening level. This becomes a learned value which you lose when you disconect the battery. Well I disconnected the battery to install the driver’s side LasFit LED low beam bulb and then the low idle, periodic stalling problem appeared.

Should you clean your Throttle Body and How to clean it on Toyotas - YouTube

I know there is one thread here where a poster said the dealer blamed the low idle and stalling on the LED lights they had installed, but that is correlation, not causal. Now I have the causal explanation and I will clean the throttle body today.
 
Closer look at air filter and no coolant contamination and it is dry. Cleaned the MAF, but it was sparkling clean when it came out. Test drive and still had low idle and a stall after warming up. Next I will clean the throttle body.

At the 4:00 minute mark of this video, he describes how the throttle body continually adjusts the butterfly valve opening to compensate for carbon and debris build up to maintain the 16% opening level. This becomes a learned value which you lose when you disconect the battery. Well I disconnected the battery to install the driver’s side LasFit LED low beam bulb and then the low idle, periodic stalling problem appeared.

Should you clean your Throttle Body and How to clean it on Toyotas - YouTube

I know there is one thread here where a poster said the dealer blamed the low idle and stalling on the LED lights they had installed, but that is correlation, not causal. Now I have the causal explanation and I will clean the throttle body today.


Hopefully you can fix it. I just had issues with my throttle not working and left me stranded. swapped out gas pedal and throttle body and think its fixed.
 
Hopefully you can fix it. I just had issues with my throttle not working and left me stranded. swapped out gas pedal and throttle body and think its fixed.

Cleaning the throttle body fixed it. It was pretty dirty. Had a 0.5" wide line of gunk on each side of the butterly valve. It took a number of soakings with cleaner, followed by work with an old toothbrush to get the stuff off and it came off in pieces and flakes.

All back together and took it for the same test drive where I would see stalling at a stop and no stalls. Idle rpm drops to between 600 and 700 rpm stopped in reverse or drive. In park the rpm is higher, up to 1000, but that was after just 4.5 mile drive in 33 F and light snow fall. I'm calling it good.
 

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