What could have caused my O2 Sensors to fail prematurely?

[Need4Camaro]

My front O2 sensors lasted 6 months before throwing the codes: P0133 / P0153

The codes set when the sensor's switching between rich and lean is too slow. To control the A/F ratio, and make the cat work, the PCM swings the A/F ratio back and forth rapidly from slightly rich to slightly lean continuously. The cat stores oxygen when the mixture is slightly lean, and uses the stored oxygen to oxidze unburned HC's and CO when the mixture is slightly rich.

Why did my Bosch's only last 6 months? I am shooting for straws cuzz I dont want to replace them and have them prematurely die again. The only thing is, is I MIGHT have a coolant leak in the intake gasket but even thats uncertain at this point.

[Hib Halverson]

Re: What could have caused my O2 Sensors to fail prematurely?

There are several reasons why O2Ses can fail prematurely.

Contamination from RTV sealer. Excessive oil consumption. Coolant consumption. Use of MMT-based octane boosters. Use of leaded gasoline. Defective sensor.

Either of those codes can, also, be caused by 1) exhaust leaks close to the sensors, 2) lack of "reference air" or 3) problems in the sensors' heater circuits.

Best bet is to use the diagnostic info in the FSM before you go buy new sensors because the chances of a defective sensor are low.

[pace2006]

Some people have reported issues or premature failures when using Bosch O2 sensors with the 3.8L. Might give Delphi or Denso brand sensors a try next time.

[2.8 Bird]

Re: What could have caused my O2 Sensors to fail prematurely?

Are you still experiencing a disappearing coolant?

Maybe you should start focusing on head gasket now. It'd be pointless replacing that and then have it fail again.

leaking coolant in the combustion chamber then into exhaust can cause your O2 to prematurely fail.

Have you changed your oil and did you see any sludge?

Or you can also open up one your valve covers and see there are any sludge there.

[transamtom1]

Re: What could have caused my O2 Sensors to fail prematurely?

Yes to everything in all three posts,you need to find the cause for the failed O2's they are just the result.

Coolant kills them quick though.

[VF1Skullangel]

Re: What could have caused my O2 Sensors to fail prematurely?

A failing head gasket.

[Need4Camaro]

Re: What could have caused my O2 Sensors to fail prematurely?

Yeah. I havent found out where my coolant is going. I was concerned though just in case it wasnt a headgasket. It doesnt matter I guess. Im about to replace the entire engine anyway. But it gets on my nerves that I cant figure something like that out.

Also when I cranked it today, it was ticking LOUD and did so for about 10 minutes until the temp gauge reached the quarter mark... any idea on this one?

[Need4Camaro]

Re: What could have caused my O2 Sensors to fail prematurely?

I...don't understand this at all :(. I checked my oil, it looks fine. This morning I cranked it and it was ticking LOUD and didnt stop at all this time so I babied it and I cant find where the sound is coming from. Maybe I have an exhaust leak...I dont know.

I checked my coolant and although it wasnt topped off, it wasnt low at all as it easily filled to the top with just a pour of coolant which means I probably didnt lose any...I dont know whats going on or what to say or why my O2's fouled out so quickly... cars suck sometimes.

[pace2006]

Re: What could have caused my O2 Sensors to fail prematurely?

Some people have reported issues or premature failures when using Bosch O2 sensors with the 3.8L. Might give Delphi or Denso brand sensors a try next time.

.....

[2.8 Bird]

Re: What could have caused my O2 Sensors to fail prematurely?

I...don't understand this at all :(. I checked my oil, it looks fine. This morning I cranked it and it was ticking LOUD and didnt stop at all this time so I babied it and I cant find where the sound is coming from. Maybe I have an exhaust leak...I dont know.

I checked my coolant and although it wasnt topped off, it wasnt low at all as it easily filled to the top with just a pour of coolant which means I probably didnt lose any...I dont know whats going on or what to say or why my O2's fouled out so quickly... cars suck sometimes.

Did you actually drain your oil or did you just looked at your dipstick? [Looking at your dipstick is not the accurate to do it.]

[Need4Camaro]

Re: What could have caused my O2 Sensors to fail prematurely?

Did you actually drain your oil or did you just looked at your dipstick? [Looking at your dipstick is not the accurate to do it.]

Just looked at the dipstick. I can't drain the oil here, the car parks on the side of a public street

[Need4Camaro]

Re: What could have caused my O2 Sensors to fail prematurely?

The knocking sound appears to be a lifter.

Still searching for coolant leak.