Alright folks sorry for the delay. I had pretty much decided already that my warm start issue is coming from elsewhere (probably fuel related because wafting propane into the intake cures it), but decided what the heck I'll do this anyway to see if any difference at all. I had already purchased the sensor.

AFM "pop that top". Red connects are the for the stock IAT (no polarity, it's just a resistor connected to E2 on the left and THA on the right)


Bosch unit with test wiring attached (I found the connector at advance auto, it's labeled "bwd pigtail" in their catalog).


Made a little hole for the wire to come through


Sensor hangin' out (sorry for shameless clean engine bay camera angle, not sorry)


Test location, very high tech, ship it!


First start was a little rough, then the ECU seemed to adapt pretty quickly and runs just as smooth as it did before.

I'll know tomorrow if it helps with the low idle on warm start issue, tonight only had cool starts which are always gravy. I also burped the heck out of the coolant system on a super steep hill in my neighborhood and got 3 good belches. Seemed to really improve idle stability more than anything so far.

Is it worth it? I am doubtful, but why the heck not try. I have to rule this out. I may also try mounting it in some different spots. Engine does seem to have a bit more pep @<2k. Maybe it does have some merit

 

I wish I could say it worked Jenny, but alas, the ice didn't work

 

Tip: You guys see that silver round circle on the AFM at the top between the black plastic cap and intake side? That's a plug that covers a trim screw to fine tune the AFM. The plug is CAREFULLY removed by:
1) Drilling a very small hole in the middle of the plug (it's soft aluminum) but be very careful not to go beyond the bottom of the plug or you'll be damaging the adjustment screw under it.
2) Install a small screw in the hole in the plug, pull the plug out with pliers.
Now you can see and adjust the AFM trim, make small adjustments at a time and remember where the original adjustment was. When done cover the adjustment screw with the original plug or (I use) a vacuum cap that just fits to keep dirt and moisture out of it. I've cured many rough idle problems doing this when everything else checks out OK.
Edit: This works on more than Toyotas, almost every vehicle that has an Air Flow Meter with a flapper door has a sealed trim screw somewhere, different location same effect. I did performance tune-ups and smog inspections for a loooong time.

 

Do you think the chirp wheezing sound might be caused by this only does it once then runs fine, it sounds like the sound is right behind the firewall on the passenger side. Like its coming from the EGR valve.

 

do you have AC in your truck?

 

No just a heater, today it is running weird like it is missing and the low idle thing is happening while running, did it while I was at a stop sign then went back to normal. Strange behavior

 

I've had this problem ever since I bought my 4Runner. It's a 1993 22RE. Cold starts are fine as the AAV boosts idle RPM, but warm starts she often idles at ~500 or less. If I let it sit for a minute or two the idle sometimes slowly creeps back to 900. Also, if I give very light throttle to 900rpm, it'll stay there once I let up. Aggressively blipping the throttle, though, doesn't work. Would be nice to find a solution for this.

 

Where are you located?

 

Springfield OR

 

I would love to get it solved too, the low idle issue just recently got worse so I pulled the upper intake off and cleaned it completely worked before but it didn't seem to have the same effect this time. Strange but curable I am sure

 

Have you tried grounding the FPU switch (harness side) while it's doing this?

 

Under the dash above the driver's side kickplate you'll see two grounding points. The lower ones are white with a black tracer, the upper ones are brown. Disconnect the brown ones, it's two wires into one connector, and look very carefully where the wire conductors are crimped into the connector. If they look black, green or any color besides clean copper, cut the connector off, strip the wire and crimp a new connector on, re-attach to ground and try your truck. It is insane the number of strange issues a weak ground will cause, and you will not see this with an ohm meter.

while you're there, the white/black wires are for your accessories, be a good idea to do that one too.

It might not fix it, but it's something cheap to try, right? And if it does fix it...

 

Thank you I will definitely check it out and see if it is the problem wouldn't be the first time the wiring caused an issue with this truck

 

😯hoping for the best

 

Update : Now as soon as the idle drops it tries to die WTH!!!!???

 

Re-adjust your tps.

 

OMG I hated that it was a major pain in the u know what. Do they get out of adjustments often

 

No, but they DO get adjusted when the ground starts going bad, then when the ground gets fixed the values change and they're out again.

I just re-adjusted mine this morning, after fixing my ground I gained lots of power, cold starts are a breeze and overall crank time when starting is under a second.
But, at a cruise about 60mph it would either want to accelerate or cut off and decelerate, even did the surge thing a few times.

 

Hey figured it out... There is a sensor above the fuel rail that talks to the ECU.... It was unplugged. Damn dumb luck, the butterfly on the throttle body was sticking and had some holes in my vacuum lines. She sounds so good and throaty now. Wow kinda sounds like a big block Chevy I had once with a cam. I did some idle adjustment also that made a big difference. It still sounds like it has a slight miss in it once in a while I think I will seafoam and grab some fuel injection cleaner to see if that helps. Might also be time for new injectors, plugs and wires.

 

what is this sensor look like or called? would you be able to take a pic of this?