Checked the IAC valve's operation by jumping terminals - Toyota Nation Forum : Toyota Car and Truck Forums

97&02camryleI4 · 03-23-2005, 04:33 PM

but I don't know if I did it right and if the results meant the IAC is okay. I warmed up the car to operating temperature and idled around 800-900. I took a paper clip and bridged the TE1 and E1 terminals. But it seemed like the paper clip didn't want to go in the terminal so I only had them make contact. Once they were bridged, I could here a different tone in the engine. My Haynes said the engine speed should increase to approx. 900 to 1300 rpm for five seconds then return to normal idle speed. Problem was that my normal idle speed was already around 800-900 so I could barely see the difference visually if the rpm went up. It did go almost to 1000 rpm but I expected that it would go close to 1300. Did I do this right? Was I suppose to make the paper clip go further inside the terminals? I didn't want to jam it in and break it.

Reason I'm testing the IAC valve is because sometimes when I start the car, it stalls immediately or struggles a few seconds and stalls. I'd have to keep the throttle open manually until I hear the rpm jump up a bit then it'll be okay.

There is another procedure to check the IAC valve connector by measuring the IAC valve resistance but I would need to rent the digital multimeter.

88 LE · 03-23-2005, 05:13 PM

Quote:

Originally Posted by 97&02camryleI4

Did I do this right? Was I suppose to make the paper clip go further inside the terminals? I didn't want to jam it in and break it.

A paper clip will fit inside the terminals. You won't break it as long as you don't shove something huge into the terminals.

Just shove the paper clip into the terminals.

97&02camryleI4 · 03-23-2005, 08:39 PM

Seems like in order to shove the paper clip into the terminals, I'd need something like needle nose pliers to open up the terminal a little before the paper clip would fit between the two fittings. Something as easy as this and it's giving me grief

But aside from the paper clip, how were my results? Does my IAC valve seem okay?

fe519 · 03-23-2005, 08:43 PM

im pretty sure its your iav thats busted... really sounds like it

mobes · 03-23-2005, 08:44 PM

What car is this on? If it's a 97 or 02 as your name implies, you have an OBDII system and need to use a code reader.

Edit: Or are you referring to a specific IAC test procedure?

97&02camryleI4 · 03-23-2005, 08:59 PM

Quote:

Originally Posted by fe519

im pretty sure its your iav thats busted... really sounds like it

I want to be almost 100% sure before I spend $200 for the IAC valve so that's why I'm performing this test. The car starts fine 3 out of 5 times. Seems to do better when it has been driven for a while. Seems to do worse when it's a cold start. So I'm open to other reasons why my car stalls only sometimes right after I start it up.

Quote:

Originally Posted by mobes

What car is this on? If it's a 97 or 02 as your name implies, you have an OBDII system and need to use a code reader.

Sorry for being unclear. It's a 97 LE 5SFE with only 52k miles. There is no CEL so I thought maybe there's no code to read. Haynes said the CEL would stay on if the problem persisted after 2 drive cycles. It would go away after 3 drive cycles if the problem is no longer there.

Quote:

Originally Posted by mobes

Edit: Or are you referring to a specific IAC test procedure?

Yes I am referring to a specific test procedure outlined in the Haynes manual. This is the 1st out of 3 tests to see if the IAC is working properly.

fe519 · 03-23-2005, 09:25 PM

try going to autozone to plug in the obdII reader and see if there is a code. Manytimes there is a code stored but the CEL did not turn on. You can take out the iav and clean it with carb cleaner and put it back and see if that will fix it... usually it does. Just make sure to replace the iav gasket

97&02camryleI4 · 03-23-2005, 09:34 PM

Quote:

Originally Posted by fe519

try going to autozone to plug in the obdII reader and see if there is a code. Manytimes there is a code stored but the CEL did not turn on. You can take out the iav and clean it with carb cleaner and put it back and see if that will fix it... usually it does. Just make sure to replace the iav gasket

Will do that soon (spring break now). I was looking for the 16-pin connector for connecting the scanner but the only one I found was right underneath the steering wheel above the foot well. Is this the correct one? Haynes said "left side of dash" so I assumed it was this one. I haven't got time to go to Autozone yet. Last time I was cleaning out the throttle body and was going to take it off along with the IAC valve but then it started pouring and was getting dark. Somehow, my 1 hour projects usually turn into 3 hours

Do dealers normally stock IAC valve gaskets or would I have to wait to special order? Gotta plan ahead so I know which day to take off the damn thing.

fe519 · 03-24-2005, 12:35 AM

the connector is right below the steering wheel... between the steering wheel and the pedals. Your probably found it... pretty much out in the open. Dealers usually stock them because the camry is notorious for the bad iav. I had the same problem as you and changed it and no problems... its been over 2 years now. I actually asked my friend when mine went out and he said the dealer fixes on the average of 2 per week... ironically they were fixing a camry with a bad iav when I was there...

fe519 · 03-24-2005, 12:37 AM

oh... one more thing, he told me this is true for the 4 cyl camrys... not so much with the V6... just for your info

97&02camryleI4 · 03-24-2005, 02:18 AM

thanks for the tips and info fe519

TehBotol · 03-24-2005, 02:28 AM

i think the IAC valve is known for being stuck because of the carbon deposit.. not as much as it being worn out.. if thats the case then replacing it doesnt solve the problem of having carbon deposit in there..

97&02camryleI4 · 03-24-2005, 02:36 AM

I think Toyota redesigned the IAC valve as to prevent the buildup of carbon deposit? I'm not sure but it would take another 50-60k miles before I'd have to worry about it again if I replace it. But I'm gonna first try to clean it.

97&02camryleI4 · 03-24-2005, 11:05 AM

I know we are supposed to buy a new IAC valve gasket when we replace the IAC valve, but...

I want to disassemble the IAC valve today and clean it but I was wondering if it would be necessary to buy a new gasket. I'm not putting in a new IAC valve, just cleaning it. I figured I'd buy a new gasket if I bought a new IAC valve. What's the worst that can happen if I don't replace the gasket?

Just need to know before taking it apart.

AHHHH! I'm 95% through getting the throttle body off but the damn water bypass/coolant hoses are so damn hard to pull off. I thought maybe if I took off the throttle body first then it'd be easier to pull off but nope. I got 1 out of 3 hoses off. The hoses I'm speaking off are attached to the IAC valve under the throttle body. It's stuck on there TIGHT! Anyone got any suggestions how I may get these off? And no I'm not going to cut them.

88 LE · 03-24-2005, 02:53 PM

Use a flat head screwdriver on the very top of the hose. The idea is to try and wedge it loose. Try twisting and pulling on the hose while you wedge it loose with the screwdriver.

If that doesn't work, use some pliers around the hose where it connects to the IAC. Twist on the hose with the pliers to break it loose. Once its loose, you should be able to pull the hose off.

Don't get the hoses mixed up. 2 of them are for coolant and 1 for vacuum.