bmxjedi

I have an 87 4runner that i recently purchased for a toy and when i bought it it barely ran (2 clogged injectors).
So i took off the intake manifold and cleaned it all out and took out the injectors to find that 2 of them were packed full of dirt... Didnt have any money for new injectors so i cleaned these out the best i could and soaked them in gasoline.
Got everything back together last night and it started right up! It runs perfect, took it to the power washer and cleaned everything all up.

ANYWAY.... when i first start the truck (warmed up or not) it will idle very low, maybe 500rpms. But once i rev it a couple times it will start idling at 1500-2000 rpms

any ideas what might cause this??

ChefYota4x4

iTrader: (5)

You can usually find other threads with similar problems.....Although, that doesn't always solve your issue, trust me, lol. Anyhow, I've read several people comment on this problem, and it's sometimes the IACV(Idle Air Control Valve). I read a thread here with a link to another site, (4wcrawler?), where a father was helping his kid with this, seemingly, EXACT issue.

One question, which I ask because I've heard many mention it upon this GREAT site...."Did you remove the TPS when cleaning out the Throttle Body?" Guessing that's caused some havoc for others. Low idle(is it rough, too? ...missing?) at first start, then 'screamin rpm's', eh? ....

https://www.yotatech.com/forums/f116...e-pain-208987/

bmxjedi

I looked through all the threads i could find, im new to yotatech so i kind of have a hard time finding things haha! I took off the TPS when i cleaned it all out, maybe a vacuum line is in the wrong spot? i dont see how i couldve done that though, i labeled everything like crazy haha! AND i didnt have any extra bolts in the end witch is always a good sign hah but ill check out 4crawler and see if i can get any other ideas. Ill check into the IACV for sure and see if thats it.

its not really a huge deal just because its not a daily driver or anything, but more of an annoyance more than anything...

ChefYota4x4

iTrader: (5)

Hey, you can test that IACV, somewhat, by starting it, cold, pinching off that vacuum hose in the front of it(had to replace mine. When I squeezed the original, it nearly cracked in half, hahaha....Oh, 25$ from the dealer for that hose, btw...and that's just ONE OF THEM, lol. Ohhhh, I love what you do TO ME, Toyota'$...>Jk, LOVE MY TOY) So, pinch it off when the truck is fully cold, and the idle should drop a good chunk. Then, warm it up, fully, and pinch it off again. When warm, the valve should be pretty much closed, so you will only see a 50rpm drop(at least that's what the book says). I took a mirror and looked inside, as well, when replacing the hose. The valve was slightly open, as I believe it's supposed to be.

Yeah, could be a vacuum thing. If you switched something, I would imagine it gets all confused and tries to compensate? If you look through my posts, you'll see I'm having one of those "WTH could this be, already!?!" type issues with my 87 4runner. ....Which is a second truck, but MY FAVORITE!

Good luck, I'm anxious to see what it is that's causing your problem.

Elevationgain

I suppose i should start a new thread, what with all the issues im having with my engine... but anyways,
I have a similar problem. my engine idle rises and drops repeatedly the frequency of it changes if i step on the brakes. i have messed around with the TPS, cleaned it, tried another one from a different engine, doesnt help.

my truck is a 92 and i recently dropped a 22re from a 91 into it. the TPS on the 91 didnt fit the wiring connector from my truck so i had to swap the whole manifold over as well.

other issues(related?):

-i noticed a small hole in the coolant hose that goes form near the thermostat to something in the throttle body, i think it adjust the idle when the coolant is warmer. the hole is not large and only leaks when i bend it a bit. then it squirts.

-i have put in 3 thermostats and each time the temperature has to get right into the red before they open... i am frantically looking for a place to pull over but then it always opens and the temp drops back down. this will continue as i drive down the hwy. although after the first time it doesnt go all the way into the red just close to. my rad has the hose to a reservoir so i believe this eliminates the possibility of an air bubble...

anyways any help would be great....


::edit::
i should note that the truck sat for nearly 4 years.

hilandfrog

from my readings in here.... "burping" air bubbles can go from "take it in to the shop" to "Never even tried, and she runs great"

So if'N it were my problem, I'd put "burping" the cooling system on the list.

I'm currently pulling my hair out on the IACV/AAV, don't take it all the way appart, it seems putting it back together is a "Top secret factory setting" and getting it close isn't an option.... Many say remove and replace

As far as sitting for 4 years, brake cylinders/ clutch parts/ vacuum hoses and from a few posters.... the corrugated elbow on the intake hose having holes in them, found only through manipulation of corrugated tubing.

Best of luck

Repo

Elevationgain

cheers for the advice,
i think i will make a new thread once ive tried a few other things. like burping the cooling system.