My check engine light came on in my truck and i took it in and they said the heating element is out of my post cat 02 sensor. So i read around and heard it was not that big of a deal since it was the post cat and only the heating element not the whole sensor. Well i was dribing through town the other day and anytime i would stop at a stoplight or stop sign or sit and let it idle it would sputter and stall and sometime die. But if i gave it a little bit of gas it would come to life but go right back to doing it ? What is my problem and how can i fix it ?

 

I am dealing with a similar problem. My truck was doing the same thing...with the stalling.
I was told it's the IAC, Idle Air Control valve. You can try cleaning it and the whote trottle body while you're at it. Or replace it.
I cleaned mine and it didn't stall for a little while, then started again. I've since replaced it. I'm now waiting to see if that actually cured the problem.

The o2 sensor is not a big deal. I did that a few years ago.

 

could you tell me or link to somewhere that tells me how to clean it ? If that fixes yours let me know i may have to order my Fastmann but i was holding off since i might sell it, but cant hardly sell it running like poo.

 

My idle is also really low, and i can hear my cold air intake really sucking hard when im sitting at an idle...sound like an IAC ?

 

Since you said you had a light come on about the o2 sensor, I would lean toward that being the problem. Heres what I know about o2 sensors... The ruck starts in a cold circuit loop to allow the o2 sensors to warm up to operating temperature (600 degrees) When it reaches this point, the computer goes into an open loop circuit and thus starts reading the voltages put out by the o2 sensors. With the heating element out, the o2 sensor can drop below 600 degrees at idle and therefore cause significant problems because the engine is trying to read the voltage output but can't. I would change out that sensor. A faulty o2 sensor can cause rough idle, loss of power, reduction of gas mileage among other things.They are not meant to last the life of the vehicle anyway. When you bring it to the mechanic, they will change that first if they suspect it because it is cheap and can cause confusing problems

 

ya but i'd rather not fork out $90 for something that isnt going to fix it...

 

Replace your IAC and your pre-cat o2 sensor. I bought mine over the counter for 50 bucks a piece, cheaper if you order it through summit or rockauto. easy fixes. the IAC right behind the TB and the o2 sensor you can slide under and get too.

Also, get a TB gasket as it's easier to change the IAC with the TB off, and replacing the gasket is like 1.50.

 

Also, my plenum is bad, so oil get's into the exhaust system, and when that oil sits on the o2 sensor over a period of time, it literally burns up. wish I took a pic of mine, but a good tip is metallic, and mine was powdery white.

Might want to dip down in your intake to check for some oil. a little bit is ok, but I call it "Swamp Intake" when your in need of the plenum kit.

 

took the IAC off and cleaned it with carb cleaner then ran sea foam through the motor, checked the bottom of the intake and there was no oil down there... the hesitation seemed to go away ill drive it more tomorrow to make sure.

 

How much smoke blew out your tailpipe?