O2 sensors

Status
Not open for further replies.
Why would a Denso representative lie to you? I am sure he has your best interest in hearts :-)

Do you think manufacturer will put a sensor which has lifetime of 30K when he is federally on the hook to provide the emission coverage for 8/80K?

You replace O2 sensor when they fail or become marginal and that is NOT based on only mileage. It is true that they can become marginal before computer throws a code but unless you notice drive-ability problems, you should leave the O2 sensors alone.

If you have more money, buy a good scanner/scope and look at the sensor output in the realtime. Then you can intelligently decide if the time has come to replace a marginal sensor.

- Vikas
 
Originally Posted By: Vikas
Why would a Denso representative lie to you? I am sure he has your best interest in hearts :-)

Do you think manufacturer will put a sensor which has lifetime of 30K when he is federally on the hook to provide the emission coverage for 8/80K?

You replace O2 sensor when they fail or become marginal and that is NOT based on only mileage. It is true that they can become marginal before computer throws a code but unless you notice drive-ability problems, you should leave the O2 sensors alone.

If you have more money, buy a good scanner/scope and look at the sensor output in the realtime. Then you can intelligently decide if the time has come to replace a marginal sensor.

- Vikas


ya i thought it seemed early as well, but i think it was more of a for peak efficiency thing. but he did have some good demos showing how much of a beating o2 sensors take, they are a very forgotten about maintenance item.
 
Originally Posted By: Vikas
Why would a Denso representative lie to you? I am sure he has your best interest in hearts :-)

Do you think manufacturer will put a sensor which has lifetime of 30K when he is federally on the hook to provide the emission coverage for 8/80K?

You replace O2 sensor when they fail or become marginal and that is NOT based on only mileage. It is true that they can become marginal before computer throws a code but unless you notice drive-ability problems, you should leave the O2 sensors alone.

If you have more money, buy a good scanner/scope and look at the sensor output in the realtime. Then you can intelligently decide if the time has come to replace a marginal sensor.

- Vikas


Yep,they will let you know when it`s time to replace. I.E my earlier post re;my daughter`s Elantra.
 
Last edited:
Engine check lights and codes can be thrown for tiny malfunctions.
O2 sensors are odd in that they can be 1/2 bad and still not throw a code. Or, you can get an O2 code and it is another system or part that is bad.
 
If you have got extra hundred or so dollars burning hole in your pocket, pick up laptop based scanner (google Alex Pepper OBD) which will plot the O2 sensors in realtime.
 
I'm with Vikas on this one. That was exactly how I was taught when it comes to O2 sensors. If your mileage starts going south, there is something else going on.
 
Originally Posted By: Vikas
If you have got extra hundred or so dollars burning hole in your pocket, pick up laptop based scanner (google Alex Pepper OBD) which will plot the O2 sensors in realtime.


I can see that with my hand held scanner.Along with many other things going on.i.e engime rpm,temp,ign.advance etc.
 
If the front (primary) sensor is switching rapidly and if the voltage swing is good, leave the sensor alone.

If the rear (secondary) sensor is switching rapidly, you need new converter.

- Vikas
 
Originally Posted By: mopar_monkey
a rep. for denso gave a class i attended once, he said o2 sensors should be changed every 30 to 45k, even if you don't have a code. it will start becoming slower to respond and if it gives false readings but is still giving them the pcm will assume they are correct and adjust the fuel trim accordingly.


Call me a sceptic but my '96 explorer had original O2 sensors at 210k miles. If the fuel mileage does not decrease and no codes why change the. Sounds like Denso wants to sell more sensors.
 
Last edited:
Status
Not open for further replies.
Back
Top Bottom