New problem with my 2000 4Runner SR5 V6.

I got off the freeway and the truck stalled. I can start it back up but I have to have my foot on the gas pedal. Once I lift off the gas pedal the truck dies. The truck runs great when giving some gas. So basically the trucks would stall at every stop light.

I did some searches and it seems to be pointed at the IAC valve. Seems logical since I can't get the truck to idle but most people seem to have hesitation or low/high idle. My idle was perfect before this happened.

How does the valve work? does it have some sort of motor in it that could of crapped out and never allowing it idle? Any other ideas? I just want to make sure before spending 200 bucks on it.

Lastly, no check engine lights at all and I have about 230k miles on it.

 

Interesting no MIL coming on.

The light does come on when the key is turned on so the bulb is working??

It happened only the one time??

Or it stalls every time you come to a stop??

I had my 3.4 every once in a while after a long drive( 60 to 80 miles) at 70mph when coming to the stop sign at the end of the ramp just stall .

Restart and all is fine.

If your IAC was acting up you would be getting the P0505 code

 

The valve is a wax based valve IIRC, and when it heats up it expands, and closes off. Could be the issue, but I do believe it would throw a code... not sure on that tho...

Either way, it def sounds like a vacuum leak, so I'd start searching for any obvious vacuum leaks, like a crack or hole in the intake tube, etc... then move on to checking/testing the IACV.

 

My check engine light definitely works. I also have a scan gauge hooked up and that didn't find any codes.

Its stalls every time my foot is off the gas pedal. Can't even start it up with out gas.

I will start looking for vacuum leaks.

Any other ideas?

 

yeah... you shouldnt need to give it throttle to get her going... sounds like a vacuum leak to me.....

 

Bare minimum check the IAC operation.

On my Subaru I had the exact same symptoms as you (except the light came on). Its IAC is a electro magnetic valve and the sliding door had so much gunk on it from over 250,000 miles that it could not move freely anymore.
10 minuets with a wrench and carb cleaner and its been fine now for a additional 25,000 miles

Little bit of time Vs. $300.00 for a new part.... Easy answer

 

When was the last time the air filter was changed or looked at at least

Last Good throttle body cleaning if the idle air passage is restricted it would need more air.

Vacuum leak tends to get it to much air increasing idle yours you need to give it more air.

If the idle is not in spec for two cycles the MIL will trip.

This is interesting .That your not throwing any codes??

With your scan gauge all the sensor reading were in spec for conditions

This is one where you need to start with the basics and do one step at a time.

You have not had the throttle body or intake off for any reason or been pulling hoses off.

 

Any tips on how to check if the IAC is working properly?

The air filter looks pretty clean. The throttle body look nice and clean too. I never had to take the TB off before its been a solid truck.

It the TPS a possibility?

I almost wish I had a engine light on....

 

UPDATE!

She LIVES!!!!

Went ahead and replaced the IAC valve with a new one. Amazon has the best price if anybody else is looking. This is what you want to get "Standard Motor Products AC197 Idle Air Control Valve". It is actually a OEM Toyota/Denso part for $128. I bought a new gasket from the dealer for $5.

The old one was pretty gunky after 225k miles, I will be very happy if the new one will last another 225k. Since I had no idle at all, I didn't bother cleaning the IAC because I figured the solenoid was shot. Since the Tb was off, I cleaned it up a bit, the hole for the idle valve had a bit of crud on it. All said, it was a pretty easy job.

So it is possible for the IAC valve to die and not have a MIL. I also did a ohm test and the old one tested out exactly the same as the new one, so that wasn't very helpful.

Thank you all that replied and helped me out!

 

Amen this this post. The dealer cost for the IAC valve was $360. Autozone and NAPA had a POS aftermarket IAC valve for $250, they assured me it was OEM.......LIARS!

Amazon sold me the Denso part for $128. It will good for another 200,000 miles.

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