Hi All,

I have a 1999 Saturn SL2 that is giving me a P0141 error code, which the
Haynes manual says is 02 Sensor Heated circuit fault. I've since replaced the
02 sensor, and after about 40 miles or so the code pops back up. I'm
replacing the catalytic converter today (vehicle has 117k on it) and hoping
this helps. Any other suggestions?

Thanks

Eric

Did you replace the correct O2 sensor? DTC P0141 HO2S Heater Performance Bank 1 Sensor 2, which means its the rear O2 sensor. Replacing the catalytic converter will have little or no effect .

I replaced both of them, upstream and downstream.

I did some searching around and found that the cat does impact this sensor.

Car is getting a cat now, either way, hopefully the SES light goes away.

Also, I used a Bosch universal, and I was VERY careful with my wiring.

Any other suggestions?

Eric

how would a cat not have an effect on an O2 code. The Bank 2 o2 sensor is basically there to make sure that the emmissions are doing its job and one of those things being a cat. So a clogged cat could definetly throw an 02 code
Edited by: sw2cam

UPDATE

Changed the Cat, cleared code, and drove home.

Had the car smog checked, and the P0141 Code has come back, DURING
THE TEST!!!! ARGH!

Other than that, the car passed all the emissions requirements very well,
looks very clean, only problem is the Service engine soon light.

So got back to the office, cleared the code using auto tap, and after
driving 40 miles home the code has come up again. Same code.

We've got a factory style 02 sensor on order. (other was splice in style),
and also a new ECU (computer) as I heard that these could be the
problem as well.

Any other suggestions??????

The code is detecting a problem with the sensor, not what's in the exhaust. If the catalytic converter is replaced, chances are the same old defective sensor will be installed in the new catalytic converter. Thus not having any effect.

Extremely highly doubtfull.

Low saturn:

I know the computer is highly doubtful but I am at my wits end trying to
figure this out. The car needs to be smogged by next Tuesday and I am
running out of ideas.

Do you have any ideas on what it can be?

Low saturn:

The cat in this car is a weld in unit.

I've replaced the o2 sensor, both upstream and downstream.

The code for the sensor didn't change. It keeps coming back with the same
error.

thanks for any advice

ah, yea i see what your talking about. It could possibly be a wiring issue rather than a sensor issue
Edited by: sw2cam