HOW DO YOU KNOW WHEN 02'S GO BAD?

[Qualitywires.com]

HOW DO YOU KNOW WHEN 02\'S GO BAD?

What kind of symtoms would you get if O2s go bad?
Rough idle?
Dying at idle when come to a stop?


What would cause your O2's to go bad?
Too much fuel?
Too much Methanol in the gas mixture from gas stations?


Thanks in advance!

 

[Ulysses]

Re: HOW DO YOU KNOW WHEN 02\'S GO BAD?

If O2 sensors go bad, you usually get poor driveability as the car goes into safe mode. You also get a CEL.

Age is the usual cause of sensors going bad.

 

[JonB]

Re: HOW DO YOU KNOW WHEN 02\'S GO BAD?

40-50K miles is about the max.

Treat em like spark plugs, and change routinely every other set of plugs.

Failing O2 can be 'invisible' and can diminish HP and NEVER throw CEL. Esp Gen 1. We had a customer claim he gained 40 HP with new front 02s and he had no IDEA there was a problem.

Routinely change Spark Plugs, Wires, 0-2s

 

[MichaelP]

Re: HOW DO YOU KNOW WHEN 02\'S GO BAD?

What kind of symtoms would you get if O2s go bad?

It was my understanding that Vipers didn't go bad until '03.

 

[Ulysses]

Re: HOW DO YOU KNOW WHEN 02\'S GO BAD?

Failing O2 can be 'invisible'.......and NEVER throw CEL

I've heard that before, I wonder why that is the case with Vipers.

 

[CAS]

Re: HOW DO YOU KNOW WHEN 02\'S GO BAD?

Failing O2 can be 'invisible'.......and NEVER throw CEL

I've heard that before, I wonder why that is the case with Vipers.

Wow LOL, that was nice and subtle .

 

[BruceW]

Re: HOW DO YOU KNOW WHEN 02\'S GO BAD?

I agree with JonB, happened to me on my Chevy. I suspect Viper O2's are no different than others. The computer only checks to see if the output voltage is within the right range. It has no way of checking if the thing is putting out the right voltage for the amount of oxygen in the exhaust.

 

[AJT]

Re: HOW DO YOU KNOW WHEN 02\'S GO BAD?

What kind of symtoms would you get if O2s go bad?

It was my understanding that Vipers didn't go bad until '03.

LMAO!

 

[genXgts]

Re: HOW DO YOU KNOW WHEN 02\'S GO BAD?

and how much are the things?

 

[Ulysses]

Re: HOW DO YOU KNOW WHEN 02\'S GO BAD?

The computer only checks to see if the output voltage is within the right range. It has no way of checking if the thing is putting out the right voltage for the amount of oxygen in the exhaust.

Thanks Bruce, that explains it.

I did a little research and short of a complete open, short or voltage out of range condition, aged and defective O2s can perform well enough so that it won't trip a CEL.

 

[Tom F&L GoR]

Re: HOW DO YOU KNOW WHEN 02\'S GO BAD?

My experience with diagnosing ~60K mile O2 sensors on a '94 was that they could be slow, they could be sending a flat, nonvarying signal for full rich or full lean, but since they didn't have the symptom for longer than the time limit of the ECU, it never tripped the CEL. Other Dodge techs agreed that unless the older OBD-1 system O2 signal is bad for perhaps 10 continuous seconds, it won't trip a light. And yes, replacing them provides a noticeable difference in engine "sharpness" as I would call it.