88 Fixit: Idle problems with warm engine

[Earthworm Jim]

My first of many troubleshoots.

1988 V6 SR5 4Runner

220k

After about 3-6 months of driving this thing in dusty conditions, I started having problems with the air intake. After about 20-30 minutes of driving, when I come to a stop and just idle, the RPMs bounce pretty erratically down to 0 then up to about 500. Many times it will just die. When the RPMs are up (i.e. when I am driving), no problems.

Went into NAPA a few weeks ago on my Friday off, and two older guys there seemed to know what it was immediately. Led me over to the shelf, put the MAF sensor cleaner in my hands, told me what to do, and sent me on my way. The next two weeks I spent overseas, then returned, saw the cleaner, and thought "Aw sh*t, I forgot what they said".

I also seem to get a check engine light after an hour or so, with no idea what's going on there. And, to add to the fun, the engine temp sensor (I've replaced the coolant sensor to no avail) doesn't seem to be functioning properly.

I've got the MAF off right now and it looks clean. A small layer of dust on the innards, but nothing that indicates blockage. I seem to remember a valve of some sort being mentioned at NAPA, but like I said... All hazy right now.

What should I be cleaning? Anyone had experience with this? What's the deal?

Thanks in advance! I tried searching for this problem and didn't see anything, I apologize if this issue has been addressed. Mods, point me to a thread if it exists and delete this one; make sure to berate me publicly first!

 

[Earthworm Jim]

BUMP

Anybody got any clues?!?! Anyone ever had idling issues?

 

[KidVermicious]

I swear on a stack of bibles and my mother's underwear drawer that I answered this once already, did you start another thread?

The MAF is the box on your air intake tube between the filter housing and the throttle body. It doesn't have to be badly gummed up to start acting funky, any sort of accululation of grease or dust can impair the sensor in there. Take it off the truck and spray MAF cleaner on everything you can find in there. If there's residue, wipe it out and spray it again. Repeat as needed until you can drink soup out of it.

I don't know much about a valve on the 3vze intake setup, but it's probably some sort of air return tube from elsewhere in the motor.

 

[Earthworm Jim]

I have not posted a thread before (EVER), but your swearing on a stack of bibles in the center of the Mormon stronghold is quite admirable, and I tip my hat to you, sir. Thank you for your help. There appears to be the thinnest layer of dust inside the MAF when I pull it off the housing. I will spray the ever-loving sh*t out of it, per your request.

I recently spoke to the NAPA official and he said to also spray the "idle air valve" as well. And "the wires", which I'll be a son of a mother[expletive] if I know what he's talking about, but God help me, I'm going to spray it.