Amir904

both my brother-in-laws' camrys are having morning start issues. since ive never cleaned the IAC valve on my 98 4runner, i think i should do it regularly too now since its a common cause of hard starting in morning. anyone do a writeup with pics for the IAC valve? i have seen pics of it and its greyish greenish color, but how exactly do u clean it? do u have to take it off the throttle body and spray with carb cleaner? i searched for a while for cleaning instructions but looks like there is no documentation even in the "tech write-ups" section.

Amir904

anyone?

MTL_4runner

I don't think I have ever seen a good writeup for that.
You will probably need to remove the TB because I think the IAC attaches with 4 screws on the underside.

If anyone has a pic of that, post it up.

Amir904

hopefully in a couple of weeks i will be doing that on my 98 4runner, and a couple of camrys. ill defintiely try to document it. i just need to find out the correct method of cleaning it first.
does the whole throttle body need to come off?

MTL_4runner

I am quite sure it does....you can PM Christian (<96 Runner>) and ask him since he's had his off a few times.

*Edit* I just checked on mine and yes, you definately have to take off the throttle body to clean the entire IAC.

Amir904

im not sure if my IAC is dirty but last week the engine died on me while at a red light. dont know what the cause of that is. ill clean it regardless, im pushing 140k.

Oscar

I had to take the whole TB off. I remember it being on the bottom of the TB. You may need to go buy a new gasket for the TB and for the seal between the IAC and the TB. Both of which are cheap.

I just tried cleaning it with Carb cleaner and a light brushing.

I got the idea from here:
http://www.iroczone.com/techartcleaniac.html

I was having stalling issues at red lights too, normally after hard accel. I went on a long trip after cleaning it and it didn't stall. BUT, 2 months later it stalled once more. I may try cleaning it again now, because I don't think I did a very good job in the rain, 6 deg C weather. I've read somewhere that the TPS may be causing the stall too, so that may be my next step.

MTL_4runner

I might have to do this myself when I get some free time and post pics and a writeup for people to follow.

igogusto

Did anyone ever do a writeup for the IAC cleaning? Do I need to replace the gasket and the seals? Do I use carb cleaner and what exactly do I clean?

profuse007

check coolant temp sensor. which engine model on camry? doesnt sound like a IAC to me.

creekfisher

I remember the FSM saying something about not getting carb cleaner on the IAC - reduces the life. FSM says to replace both gaskets - cost about $5.00 for both.

I have the parts - just need the time.

MTL_4runner

If you have a scan for serviceing the IAC in the 1996 FSM I'd like to see that because I couldn't find anything in there saying anything about not using carb cleaner on the IAC (or ISC as it is sometimes called) for later year trucks. I'm not sure how you'd do that anyway because as soon as you use carb cleaner to clean the throttle body, I guarantee alot will go into the port for the IAC air bypass. I agree with the gasket replacement because by now most of the gaskets would be too brittle to reuse anyway.

creekfisher

In the 1996 4runner manual Pub# RM480U on page SF-24:

CLEAN THROTTLE BODY (after it is removed)

(a) Using a soft brush and carburetor cleaner, clean the cast parts.

(b) Using compressed air, clean all the passages and aperatures.

NOTICE: To prevent deterioration, do not clean the throttle position sensor and IAC valve.

All I can do is tell you what the FSM says. I'm new at this and trying to figure it out as I go. This could be one of those things that everyone ignores without consequence.

Anyway, the FSM doesn't say anything about cleaning the MAF but people clean it with electronic cleaner. So, I was thinking that I would use electronic cleaner to clean the IAC.

MTL_4runner

Thanks for putting that up so we have what Toyota recommends anyway. Cleaning the IAC with a can of CRC contact cleaner won't do hardly anything to remove the carbon buildup that causes the IAC to not function properly. Carb or top end cleaner will remove the carbon and should restore most of the performance. The IAC is nothing more than a cast housing, a DC stepper motor and a metering cone (often made of just metal or rubber/metal). None of those can really be hurt by the use of carb cleaner (if that were true you'd also see alot more people with issues who clean their throttle body regularly like I do). I haven't done it on my truck, but I have definately done this on countless other vehicles while working as a mechanic (often as part of my routine when doing a tuneup.....I used to get comments like "wow, I can believe how smooth the car is now" or "man, the car used to feel like it was going to stall at idle, now it just purrs"). Cleaning this device is not a "cure all" either though......it is just in some cases it has gotten to where the device just doesn't function at 100% and it will affect the idle speed.

The manual is correct not to ever touch the TPS with anything, if it is malfunctioning, replace it outright. I think the FSM may be referring to the electrical portion of the IAC and that case I agree with that as well, you only need to clean the casting and the metering cone (don't mess with the motor at all). Unfortunately the FSM does read a bit vague.

igogusto

Anyone happen to have the part #'s for the gasket and the seal. Trying to explain to the guy at the parts counter at Toyota, will take forever.

creekfisher

Thanks for the info Jamie, it's good to know. You have de-mystified some of this for me.

The numbers on my invoice are:

TB gasket: 22271-62040
IAC gasket: 22215-62180

igogusto

Thanks Creek and MTL. I will try to get the parts tonight and I will let you guys know how it goes! Another stupid ? Does anyone know the torq specs? I am not sure if it is in the manual, I am at work, so I can't check.

creekfisher

13 ft-lbf for the four TB bolts/nuts.

99runner4me

I cleaned mine a while ago and posted something about it. I guess no one noticed. Hope this helps.

https://www.yotatech.com/forums/f123/re-3-4l-v6-hard-start-hot-cleaned-iac-pics-92286/

igogusto

Thanks for the part #'s. I got the parts tonight. Not a mere $5 it was $17!!!

Sorry 99runner4me, I searched the Forum and did not locate this post. Thanks for posting the link again, it will deffinately help me out!!!!

I'll let you know how it goes.