Oxygen Sensor

[tsubaki]

It can cause several things to go nuts, besides bad mileage. The Ford wiring system seems to be a little less sensitive than most, been running around for 2 years with a bad one on a F150 V6 I drive.
Had a Chrysler minivan, the dealer convinced me it was a bad transmission, 2 weeks later did the same thing, ended up being one of the sensors.
The Jeep Cherokee suddenly ran like crap, wouldn't idle or accelerate, smutted all the plugs, had to change 2 sensors to fix the problem.
Try to remember what the code number was or the defining sensor, you should have 4 on that thing, some are a booger to get to and some are in the open easily accessed.

[parishht]

If it is the sensor, then search on google for cleaning the sensor.

Family Handyman or Mechanics Illustrated did a story on how to clean the sensor,
because some unscrupulous mechanix where charge for a new one with installation,
when in fact it just needed a good cleaning.
It is a piece of wire tha gets a shelac coating on it and when the coating gets too think,
the electronics think it to be bad.
It will affect your milage, if I recall from the article.

[reelapeelin]

If you can get to the end of the sensor, spray it good w/some contact cleaner...that'd be my first try at it...

[Franco]

Okay guys, now you are poking around in my area of knowledge.

An Oxygen sensor is mounted in the exhaust system, some vehicle have multiple 02 sensor. Tey measure the amount of oxygen in the exhaust gas and it generates a voltage signal that the engine controller uses as a signal to alter the pulse width on the injectors to control the air/fuel ratio.

They are screwed into a boss in the exhause pipe and can be a pain to get out, they usually require a special 6 point socket to remove. As far as cleaning one, that might be a bit difficult as they run at such high heat that anything that would end up on the business end of the sensor will turn to carbon, and carbon is very hard at best to remove.

IMHO, If I went thru all the trouble of determining that the 02 sensor is bad, and took it out, I'd likely spring for a new one.

Just sayin..........

[tsubaki]

I'm agreeing with Franco about replacing it but then I'm just lazy.
If I have to remove spark plugs, they get replaced. If I have to check the air filter, it gets replaced. If I have to take a taillight lens off, the bulb gets replaced.

[reelapeelin]

Originally Posted by Franco

Okay guys, now you are poking around in my area of knowledge.

An Oxygen sensor is mounted in the exhaust system, some vehicle have multiple 02 sensor. Tey measure the amount of oxygen in the exhaust gas and it generates a voltage signal that the engine controller uses as a signal to alter the pulse width on the injectors to control the air/fuel ratio.

They are screwed into a boss in the exhause pipe and can be a pain to get out, they usually require a special 6 point socket to remove. As far as cleaning one, that might be a bit difficult as they run at such high heat that anything that would end up on the business end of the sensor will turn to carbon, and carbon is very hard at best to remove.

IMHO, If I went thru all the trouble of determining that the 02 sensor is bad, and took it out, I'd likely spring for a new one.

Just sayin..........

Well then...let's sh!t-can the thing about sprayin contact cleaner on the tip...the Pubah has SPOKEN!!...LOL!!...

[C YENSEN]

Ferm...98 explorer, 5.0 litre V8, 158,000 miles.

oh and the darn ABS light wont go off either???

thanks for the input fellas

[KEEPINGITREEL]

What is the code? Most O2 sensors also have a heater inside them, so that it takes less time to go into closed loop operation(ECM/PCM controls injector pulsewidth to reach proper air/fuel mix, instead of running on a preprogrammed parameter.) If you haven't noticed a drastic change in fuel economy, than I prob wouldn't replace it yet. Just becasue the heater dosen't work, dosen't mean the O2 side isn't functioning.

[THEFERMANATOR]

Originally Posted by C YENSEN

Ferm...98 explorer, 5.0 litre V8, 158,000 miles.

oh and the darn ABS light wont go off either???

thanks for the input fellas

Most likely the ABS light is the vehicle speed sensor in the rear end(very common issue), but would need to know the code to be certain. As for teh O2 sensor, I did a quick parts check and it appears as though that vehicle uses 4 of em. So saying it needs an oxygen sensor can be costly as they normally cost about $70 EACH(X4 is $280 for a guess as to which one it is). And at 158K miles there is always a chance that one of your cat converters is going bad and that is popping the code. Does your exhaust have any rattles in it? If so then I would be suspect of a cat converter. Also if you have a bad O2 and continue to drive it you can burn a cat converter out as the PCM has no way of knowing how it is running the cat converter, and they tend to melt down once you get beyond about 1580 degrees(1480 is what you normally want to maintain as the upper limit for longevity though). And as stated, it could simply be a heating element gone out. This kind of failure is the most common, but can lead to problems as well.