I would not assume a tooth if miss fire is random and you have power.. Possible dirty plug or other... If you get a code eventually, get the freeze frame data and see what else you see.

 

Thanks Steve, ill let you know.

 

Steve, it did kick a code. Po141. Downstream heated 02 sensor heater circuit fault. (Bank 1) I have a few questions on this. First, whats the difference between the sensor heater circuit and the sensor itself? Regardless, id have to change the sensor, correct? Secondly, could this cause white smoke at idle with a horrible exhaust smell? Third, could my cat. be clogged? Finally, if the cat is clogged, will this cause my sensor to go bad again? Sorry for all the questions.

 

Forgot one more question, which side is bank one? Driver or passenger?

 

Passenger.

 

Thanks pdq, what about all of the other questions i posted before that?

 

The sensor won't generate a voltage until its up to something like 600 degrees in temperature. So these "heated" oxygen sensors contain an electrical heater to get them up to temp quicker.
Not necessarily. The heater O2 heater circuit may not function if the wiring harness contacted the hot exhaust pipe, shorted to ground, etc.
Anything is possible. But the white smoke and horrible exhaust smell might be causing your O2 sensor problems.
Prolly not. The P0141 is the sensor upstream of the Cat, passenger side.

 

Po141 says downstream? But its the upstream sensor? The one closest to the exhaust manifold?

 

Mike, I think the P0141 is the rear O2 sensor... I believe the front one is P0135... on determining what sets the code, I think PDQ is right that you might have a separate problem that is causing the O2 alarm... White smoke can be burning oil or water vapor. You might check the tail pipe for tell tale signs... And the smell might help narrow it down. A problem like that might keep the O2 sensor from warming up properly. ............. check your radiator tank and engine oil level.

 

Steve, thats what i thought the code 141 said was bank 1 downstream, so thats the one after the cat on the passenger side? White smoke, its always done it a little, just started getting worse, only if you sit at idle for a long time. (Mostly in park) i need to do a compression check, maybe my rings are worn. It has 250,000 miles on it. Still runs good though. Can a clogged cat cause all this smoke? I was told a few years ago it was partially clogged, maybe it way clogged now.

 

Thanks Mike.
You're right.
My bad.

 

Mike, I don't think a clogged CAT is CAUSING the smoke. I think you have a motor problem ( worn rings / etc... as you said)... that might be clogging the CAT AND causing the smoke. The CAT is not the problem, it is the result. If your asking, if you should change it ........... I don't know... It wont make it stop smoking, but it might make it run better .... I don think you have a CODE leading you to believe the CAT is a problem.

 

Thanks Steve.

 

Steve, update:
After checking the plugs ( i changed them anyways) and changing out the coil packs ( for this little idle miss) i checked the injectors (good), did a vacuum check (good, sitting steady at 20 hg, which kinda makes no sense after what i found. I found the main pcv tube to the back of the intake manifold (under the IAC, for the pcv system) cocked ever so slightly in its boot. I straightened it out and the slight miss is gone. Thanks for all the insight. Im still working on the smoke issue that comes out every now and then at idle.

 

that don't sound too bad for a 17 year old truck with 250K miles on it !