thook

Possibly that's why the coolant lines, but I can't verify anything you or I have figured. It seems the techs at Toyota don't know much about the older models like ours since they don't work on them much....or AT ALL..lol! Then again, maybe I just haven't talked to the right person, yet.

I've thought about those coolant lines and what you're suggesting, but it seems to me that might be what the coolant temp switch is for on the thermo housing. That's all I can surmise since this switch seems to serve no purpose for anything else. (I'll have to hunt for a wiring diagram, on that). The other thing is the element on the AAV seems to work only one way.....to heat and not detect temps. There's only two wires to it, after all, and one is voltage and the other would have to be a ground. Look at heated O2 sensors, for example, on later models. There's four wires; one to heat and it's respective ground, and another for signal/voltage with it's respective ground. Again, I don't know...just figurin'. Soooo, if the AAV element does nothing but heat, I can't see the point in the bypass coolant lines. How does THIS sound?

thook

Okay, I think I understand what you're saying.

The coolant lines would have to be a "preheater" for certain "in between" temp conditions so the ECU wouldn't have to work as much to heat when/if needed.

Camrog91

What if you don't have the coolant lines going to the iacv hooked up? Would this mean that the valve isn't working because there isn't coolant going into it? Thank you

pcmentor

There is an electric heater on the valve the water I guess keeps the valve hot when you shut down temporarily

3cRider

Bringing this one back from the dead. For the life of me I can't find where to buy an I.A.C/Auxiliary Air Valve for my '84 Yota. All of the online sites show every other part except this. Can anyone drop me a link or two? Or perhaps give me a tip?

I apologize for the brainfart, lol, I've been looking for an hour now and can't even locate one for sale online.

Thanks all

pcmentor

You may not need one unless the water tubes have fell off or the heater doesn't heat up. Did you connect it directly to the battery?

3cRider

Well, I managed to get the part number off mine. In case anyone in the future has the same problem, use this number in your searches:

22230-35010

toyota4x4907

Is your '84 carb'd or efi? cuuuuuuz carbs dont use AAV/IACV

94toy22re

I was searching for surging problems for the 22re and a post came up on IH8MUD.
not my pics
http://www.flickr.com/photos/steve-wilson/4169509829/
http://www.flickr.com/photos/steve-w...n/photostream/
http://www.flickr.com/photos/steve-w...n/photostream/

I took mine off and cleaned it and the surging has stopped.
Douse anyone know what that valve is called?

thook

Um, where is/was it? It looks like it's just a vacuum port that goes into the plenum. If I'm thinking right, it's for the PCV.

thook

Oops....didn't realize there were other pics along with the first one. The first link you provided was the only one that worked. I had to click on the other pics in the flickr page.

Anyway..........

I'll be honest.......it's actually been a while since I've looked at my 22re. And, I've blinked a million times since then. So, I'd have to go look at my motor to see what's going on. I probably know what it is, but.....againl....I need to go look. I'll post tomorrow if no one else does first, or if you don't find out first.

94toy22re

Its a coolant line that goes to the iac and then into the thermostat housing. it had black junk clogging the port and that was causing my idle surge.

fire5

Pcmentor-how did you bench test your air valve?

thook

I have to admit....I've forgotten what that valve is called. However, if you PM a fellow that goes by 4runnerx3, he's got the goods. He'll have a blow up of the part and what it's called.

thook

This site http://www.autoshop101.com/ goes into testing. Look under technical articles and, then, under air induction system article 21 EFI #2. The FSM goes into it, as well.

However, you did ask for a bench test. What do you mean exactly? Do you have the part removed from the motor?

Philbert

iTrader: (2)

I came across this thread while trying to diagnose a very rough idle when cold. I just wrapped up a new head/HG/Supra AFM job and replaced all the coolant hoses, and the T stat. Been driving it about 200 miles so far and experiencing a really rough idle at cold start that I never had before.

I have a 87 4runner and the IACV is the kind that bolts to the bottom of the manifold and has 4 hoses attaching to it (not the all metal one first shown in this thread, but the second one that has metal and plastic construction).

Reading through this thread made me wonder if the IACV might be the culprit since this happens when COLD, and it seems fine when warm.

Here is my build thread (last page or so describes what's happening):

https://www.yotatech.com/forums/f116...2/index14.html


Here is a video of it (4 mins long) of starting it cold and a rough, low idle:
http://s1354.photobucket.com/user/ph...031ed.mp4.html

So, here's a synopsis of the symptoms so far:
- First start after all the work: hard starting, took a while to start but finally did and ran a little rough and low RPMs - about 500 or so. Gassed it a few times while warming up to keep it alive. Once warm, seemed fine.
- First real drive and warmed up: Seemed to run fine when warm but at stop lights it would do this looping thing where it would be at 800 RPM, then climb to 1200, before dropping back down the 800 - this whole loop took 3-4 seconds and kept going.
- Second real drive, got it warm, then pulled over and adjusted DOWN the idle screw on the TB to about 750 RPM - the surging issue above disappeared.
- Since then, I'm fine when warm (about 750 RPM) but all my cold starts are really rough. The idle stays around 100 RPMs as it's getting warm (see video).

I've tried messing with the idle screw when it's first warming up but while it does affect the idle, it's not changing it that much and it still runs really low/rough even when the screw is backed out, giving it the most air possible (right?).

The blue plug on the back of the IACV is plugged in - I checked again last night.

I don't think it's a cold start injector thing since I'm not getting an error code, and well, it's pretty warm here you know But I don't know if I'm just assuming and wrong there.

When I filled with water (no coolant yet-just distilled water while I do all this testing), I had the heater on full and the radiator neck open until warm, but this was on FLAT ground - wonder if that could be my issue? When warm, the temp goes from 180* to 210* and in between, but never over - could be air in there? But if so, why is it causing the cold start issues - Since the T stat is closed when cold, coolant is moving through the system, so would air have an effect when it's all cold??

Could be that I adjusted the throttle wrong when I set it up (I used 4crawler's guide and turned the screw till it was flush with the spring, then another 1/4 turn)....maybe needs more? Thinking out loud, this couldn't be it because it seems to idle fine when warm, and it wouldn't if the throttle plate were not open enough at idle, right??

My short term plans are to:
- bleed the system of air on a slope while warming up
- Do a vacuum leak test with carb cleaner


Matthew/Thook - you seem to be the expert on this so I'm hoping you have some sage advice for me

Thanks,
Phil

pcmentor

You might try unplugging the Cold start injector on the plenum when cold and see if there's any change in starting. I did this and it was very hard to start. Vs plugged in it starts immediatly cold. Use a pick to remove the wire clip on the CS Inj electrical plug to make removing easier.1985 22re

Also check for pinched CS inj wire.

pcmentor

I never got this mssg. Sorry.
It was a few years ago I think I used the FSM for 85 and did what it said. The way it seemed was once it is adjusted it should stay that way indefinitly. Let me know if you still need help.

pcmentor

I believe the air valve probably can't cause surging, as though it was opening and closing rapidly. It closes slowly as it warms up and doesn't flick open but opens slowly as well. I had a surging idle on my 85 22re and adjusting the valves(the ones under the valve cover) smoothed it out and was able to hold a 750 idle. I think they were too tight.

pcmentor

Thanks for the link, it is similar format to the 3 autoshop texts I have and is a great Toyo reference.