"service engine" '94 intrepid

My '94 intrepid service engine light is back on after many years. When I
went through the codes I found "recently disconnected battery" which is not
true, but I'm not worried about, and 33, which I believe is O2 sensor. I
found that both the right and left were replaced around 97 / 98. Do they go
bad frequently? What's the negative effect of not replacing them.?
Thanks,
mm

 

O2 Sensors should be replaced ever 50 to 75,000 miles.

 

Possibly your batt. is getting weak (or a high resistance connection) -
computer may have seen batt. voltage dip below the threshold momentarily
(during a startup for example).

I think continuing to drive with a bad O2 sensor often leads to having
to replace the catalytic converter.

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
adddress with the letter 'x')

 

When you check the codes by flicking the key three times, "12" means
"Start of Codes", not necessarily "battery disconnected recently".

33 refers to an open or shorted condition in the A/C clutch control
circuit, not the O2 sensor. O2S-related codes include 21, 51 and 52.

The negative effects of driving with bad or "still good but sluggish and
lazy" O2 sensor(s) include reduced fuel economy, poorer driveability and
performance, and increased exhaust emissions.