2005 check engine light

So I went in today and I had my check engine light read. For a brief history my check engine light has been coming on and off for about 3 months. Everytime Im about to get it read it turns off. One more interesting thing is that when it comes on I lose my traction control and all those lights also come on. Well the read today said o2 sensor was failing. The tech says these trucks (V6) have 4 o2 sensors, is this correct? He couldn't tell which one it was or how many. I have a magnaflow exhaust which he thought might be the cause. If my o2 sensors are indeed bad could this be responsable for bad MPGs? Thanks to anyone who can give me some advice.

 

you shouldn't need the check engine light on to read the code. the computer should store the code for future refrence....

 

well the only thing i can say if that if you just have the muffler then no because the o2 sensors are further back closer to the front of the truck. if you have a cat back exhaust then maybe but i doubt it.

i dont know about the 4 o2 sensors i have a 4 banger and i think i have 2 of them so i would seem right that you have 4.

other than that i have no uead how to check the sensors, good luck on finding out

 

I changed the oil 2000 miles ago. The tech said the computer was telling him that the o2 sensors before and after the cat were reading the same.. Sorry I don't know anything about this and I bought the truck with the exhaust already installed. Could an oil change make the check engine light come on?

 

Yes, V6 has 4 O2 sensors. Pretty sure you should be able to tell which ones are gone by reading the code.

 

Did they tell you the exact code?

 

No he didn't tell me the exact code and he did erase the computer. Is replacing an o2 sensor considered a DIY job?

 

Not sure how many 02 sensors, 4 sounds right. (might have read that on here before) A bad o2 sensor can have a negative impact on your mpgs. It monitors oxygen levels in the exhaust and tells the computer what type of fuel/air mixture to use.

 

I think you must be referring to the maintenance light. The light that is coming on is the CEL. And it comes and goes a couple times a month. I reset the maintenance light a few weeks ago.

 

Yeah that would be great thanks. I don't think that it is anything serious because the truck still runs fine I just lose traction control when it is on..

 

It may be the TSB that Toyota had with the catalyitic convertors on our trucks. I had the same problem, Check engine light came on and it read O2 sensors. They screwed me over cause I had aftermarket headers so they told me to F off even though it was their cat that was jacked up and not because of anything I had done. May be worth a shot, make them give you something for free

 

Do you think I have a chance if it is out of warranty?

 

Haha. I also have a 04 4runner and my wife told me "Babe, my engine light has been on for like 3 months..". I was thinking you have got to be kidding me, 3 months and you are telling me now??? Luckly it was the oil change light and I just reset it. I did notice one time that right before it came on my truck was idling at 500 RPMs when it is usually at about 800. It was a little rough at idle and then the light of doom came on!

 

No idea man, if its a defect it might but I dont wanna say.

 

I have to disagree this is a diy job.I have replaced more o2 sensors than i can count and never needed a welder.From what i have seen there are two styles of o2 sensors.One the sensor itself has threads on it unscrew and screw back in make sure to have the connector unplugged while doing this.The other like on my 99 taco had two nuts that held it on.If you do this yourself get some pb blaster and soak it overnight prior just to be on the safe side.