ISC = idle speed control. IAC = idle air control.

To me their both the same, just different names. I've always called it a IAC or IACV (idle air control valve).



3S-FE and 2VZ-FE use a AFM (air flow meter), not a MAF (mass air flow).


Specs (3S-FE)
------------------

1-2: closed with starter running and measuring plate open

5-6: 200-600 ohms (measuring plate fully closed). 20-1200 ohms (measuring plate fully open).

5-4: 200-400 ohms.




5-7: 10-20K ohms (-20C, -4F)

4-7K ohms (0C, 32F)

2-3K ohms (20C, 68F)

0.9-1.3K ohms (40C, 104F)

0.4-0.7K ohms (60C, 140F)



While your at it, check the ECT (engine coolant temp) sensor.



Try cleaning the IAC first, before you go replacing it.

 

IAC cleaning

whats the best way to clean it, take it off the throttle body and use compressed air, or soak the hell out of it with cleaner? Or how would you do it?

I checked all the AFM ohms and they checked out fine but my IAC resistance was around 18.2 ohms, not between the 16 and 17 ohms listed. I pray cleaning the IAC will solve my problem, also will I need a new gasket afterwards if i'm careful taking it off?

 

whats the best way to clean it, take it off the throttle body and use compressed air, or soak the hell out of it with cleaner? Or how would you do it?

I checked all the AFM ohms and they checked out fine but my IAC resistance was around 18.2 ohms, not between the 16 and 17 ohms listed. I pray cleaning the IAC will solve my problem, also will I need a new gasket afterwards if i'm careful taking it off?

You will need a new throttle body gasket, but you can re-use the ISC gaket. It's rubber, not paper like the TB gasket.

 

I would not "immerse" a part like this one.

I'd clean the throttle body, the passages, and the moving parts that control the airflow with throttle body cleaner, such as CRC makes in the red and white spray can. You can use a cloth soaked in the cleaner or a toothbrush to scrub the parts, if you put on safety glasses. A toothbrush will cause small particles of the cleaner and carbon buildup to be flung into the air, and you don't want it land in your eyes.

 

i bought some sea foam deep creep and will clean the tb tomorrow. to clean the IAC would it be correct to spray some in the IAC hole for 1 or 2 seconds? should I also unplug the IAC harness to prevent from frying it somehow?

thanks

 

I'm not familiar with that cleaner. I like to remove an IAC most of the time and spray the cleaner through the passaages that allow air to flow around the throttle butterfly. I also clean the pintle when it is so designed.

You can remove the TB as suggested above and have an easier time, replacing the TB gasket, or you can do it in place. Sorry I can't volunteer to go out to the car with a flashlight and make more specific recommdations.

If you keep the key off, there should be no problem with frying.

 

I'm not familiar with that cleaner. I like to remove an IAC most of the time and spray the cleaner through the passaages that allow air to flow around the throttle butterfly. I also clean the pintle when it is so designed.

You can remove the TB as suggested above and have an easier time, replacing the TB gasket, or you can do it in place. Sorry I can't volunteer to go out to the car with a flashlight and make more specific recommdations.

If you keep the key off, there should be no problem with frying.

The Seafoam co. makes deep creep and it's quite good. It lubricates as well as cleans. I used it on my TB and ISC with good results.

 

sweet, Ill let the car warm up for a bit, turn the car off, then get to cleaning. thx guys

 

I'll have to look for "deep creep."

Thanks for the tip. :thumbup:

 

http://www.toyotanation.com/forum/t157470.html

Here's something to get you started on this project. Deep creep is just the regular seafoam in a spray can. Normally its best for everything including the brake-hose soak treatment. Its much easier than pouring liquid in the hose and risking breaking something expensive like a piston.

If you have compressed air, i'd use low pressure (30 psi) and blow some sea foam into the IAC hole and let it soak for 10 minutes, then blow it out some more and then you are done with that.
Bitter experience has taught me not to take things apart more than you have to, unless you enjoy fixing stuff that wasnt broke before.

 

http://www.toyotanation.com/forum/t157470.html

... Normally its best for everything including the brake-hose soak treatment. Its much easier than pouring liquid in the hose and risking breaking something expensive like a piston.

The "brake-hose soak treatment?"

 

marc780 posted a good diagram and picture of the IAC at:
http://www.toyotanation.com/forum/t144688.html

While you're in the neighborhood clean out the throttle body. Auto Zone has a WEB page on throttle body cleaning at: http://autozone.com/servlet/UiBroker...3d801574ae.jsp

The EGR valve is nearby too. Don't have a link for cleaning it. They're out there.

Kep

 

The "brake-hose soak treatment?"

You pull the vacumm hose off of the master cylinder and shove it into the seafoam. The vacumm pressure will suck the bottle dry and works its way through the engine.

 

Ah.

OTC makes a kit for that where you control how quickly the fluid goes into the manifold, in order to avoid hydraulic lock from accidentally getting too much cleaner into a cylinder in liquid form.

Sounds liike it would get the cleaner in there though, and then you could shut it down and let it soak for 30 minutes.