Camry 2002 V6 occasionally dies on idle

[laleyan]

Hello, I posted this in the general forum but there was a suggestion to post it here so here you go:

I have a 80k Camry that started to die from time to time on stop lights. The car performs great. No check engine light but occasionally after relatively long drive and engine is hot, it just dies when I stop. If I turn the ignition and press the acceleration pedal 1/3, it turns back on, but if I do not force it 1-2 times to high RPM it dies again. But once I force it, it goes back to normal and performs great. It happens 2-3 time per week. The rest of the time the car keeps very sturdy idle. No fluctuation of RPM or anything that may show signs of instability. This is what I have done so far:

• <LI itxtvisited="1">Checked the fuel line and fuel filter – clean and performs great. I doubt this can be the problem because the car performs great on high RPMs. <LI itxtvisited="1">Removed and cleaned the throttle body. It was dirty and now it is totally clean, but did not resolve the problem. I had to reset the computer after the cleaning.<LI itxtvisited="1">Removed and cleaned the Exhaust Gas Recirculation (EGR) Valve.
• Cleaned the MAF sensor.

I know this kind of a problem can be caused by Idle Control Valve (ICV) but I do not see it on this model.

Few days ago I had my OBD II reader connected while I was driving, and I noticed when I stop at stop lights my RPMs are consistent per stop but differ from stop to stop. For example I will have 630 rmp at one stop, 680 at the next one, 600 on another but whatever it is it just keeps it consistent during idle (does not fluctuate at all even if I turn on/off the AC) One time it went down to 300 and was shaking but did not die. It stayed on 300 for about 8-10 sec until I pressed the gas peddal and RPM went back to 680.

Do you know where exactly the IAC on the 2002 V6 Camry is?

This is how my car and the throttle looks:

http://www.jbcarpages.com/toyota/cam.../picture14.php

http://www.justanswer.com/view_image...ottle_body.gif

What else can cause this kind of a behavior?

[LoudCamry]

spark plug??
My tacoma truck idel get low somtime and shut off,

or did you have a new battery and it is trying to learn itself

[laleyan]

The spark plugs are doing great and the battery is the same one. I did the re-learning after I cleaned the throttle valve but nothing changed.

When th eidle gets low it is not like when I stop to start going lower and lower but it just goes directly to a vely low RPM almost like it is predetermined to go that low. And again, this hapenes only 2-3 times a week considering the fact that I probably make at least 50 stops per day. I remember when it first did it was on a very rainy day while I was stuck in a traffic a year ago. Then it was doing it once every couple of months but now it is much more often.

The symptoms are leading to the idle controll valve but I have to localize it first in order to clean it.

[mxsmith]

There is no mechanical IAC on this car. Did your remove the throttle position sensor? The throttle may need to calibrated or aligned. Software drives the throttle motor and provides the IAC funtion.

[laleyan]

That explains why I cannot find the IAC valve. I did not remove the throttle position sensor and I do not think it is a calibration issue (unless the sensor is shot) because 99% of the time the car holds very sturdy idle. I realized that when I cleaned the MAF sensor, I actually cleaned only the temperature sensor. So 2 days ago I cleaned the MAF wires and seems like the car cruizes smoother. I cannot say if my idle problem is fixed because it does not happen that often and it did not hapen for the last 2 days. Since than I'm comuting with my OBD reader plugged in and my Absolute Throttle Posision stays at 12.9% at idle. Very ocasionally on some stops stays at 12.5% but the idle RPM stays wheere it should be. I will keep you posted. I'm also open to any suggestions of what else may cause this problem.

[mxsmith]

You may have got it with the MAF. Have you looked for a vacuum leak?

[laleyan]

Yes, I checked for vacuum leak and there is none.

[mxsmith]

After I made that comment I thought - a guy with a scan tool has probably already done that check.

[PRINCESS PEACH]

check your spark plugs and wirings.

If your car is dying after coming to a stop, it might be the coils.

[laleyan]

The spark plugs and the coils are in great shape and working perfect. If this is the case usually the engine will hesitate, which is not my case.

I think I mentioned that in the beginning of my post but I have removed the EGR valve and the EGR sensor from the valve, and cleaned them two weeks ago but that did not fix my problem. It is really hard to clean directly the EGR valve because ot the curvy pipe

AlmightyCamry777, which sensor with 3 screws and O-ring are you referring to?

[laleyan]

Just a quick update: i have not done any additional cleaning yet but this evening at one stop on idle I got P0174 - System Too Lean (Bank 2). This is the first time I got any code. It did not cause any idle problem and the car performed great during that stop and after that. I cleared the code and it did not come back. Shall I suspect the Bank 2 O2 sensor since the Bank 1 did not report P0171?

[RandySolara]

o2 sensor isnt a big deal at all, sound to me the problem causes is Fuel Injection or Coils, Sparkplugs. most of my customers leave the Check Engine caused by o2 sensor there and drive for year to years, my old Camry sadan and Camry Solara had the CEL for the o2 still, and its still there for a long long time. Hope u find out and fix it. yep only can guess and guess on an online help cause we dont have the car to look into it. good luck brother.

[darksparkz]

Make sure the throttle body is clean and doesn't have carbon buildup, clean the throttle plate itself too. The post cat O2 sensors don't affect anything but emission, but not for the sensor 1's. The fuel control heated O2 sensors may affect it too. A scan tool should be able to monitor the heated O2 sensor's voltage, from 100mV (lean) to 900mV (rich), which in turns affects the injectors, which might be the idle issue.

Check the TAC, throttle actuator control too, its the brass butterfly inside the throttle body.

[laleyan]

Thank you for the suggestions!

Yes, the throttle body and the butterfly are sparkling clean. It use to have a lot of build up, and after the cleanup I had to reset the computer because the idle RPM was over 1500 with CEL ON.

I gues after the MAF cleanup I got the O2 CEL because the car was still learning. I also measured the O2 sensors and I got simmilar curve and reading on both of them (bank 1 and 2) between 0.2V and 0.8V. So the mixture/O2 sensor should not be a problem.

Last week was very busy and I made over 350 miles. So far I did not experience any idle problems nor CEL. I can tell that the MPG is better since I cleaned the MAF sensor. I use to get 340 miles per tank and now I reached 370 and the gas light is not even on yet. This is in Los Angeles local driving. I will keep you posted.

[islandboy57]

http://www.topix.com/forum/autos/toy...GC5T4DHVFS52CS

I wonder if you're experiencing the beginnings of the throttle body failure that some other Toyota owners have experienced? No CEL could mean no, but it can't hurt to read up and draw your own conclusion.