o2 Sensor woes: Loren and others please help

[phaphaphooey]

I got a Cel last week on my 2000 986 and had it read at advance auto parts. it was a 1115 code so i searched and found Loren's instructions for testing the resistence between pins 1 and 2 and a pin and the o2 sensor housing. both precat sensors tested out of range between pins 1 and 2, one side testing at 2.9 and the other side testing at 3.1. to the sensor housing was infinite, which was the desired reading. i had already ordered a new sensor and tested it on arrival; it tested within the correct range. i replaced the sensor that had the most anomalous reading. today i get a cel again and have it read. codes 1115, 1119, and 1033 pop up, apparently indicating that both the old precat sensor as well as the new precat sensor that i replaced are failing to preheat and that the new sensor is "aged". am i looking at a bad connection here for the new sensor? should i probably replace the other precat sensor as well? thank you for your time.

[phaphaphooey]

still dealing with this more than a year later. fun times in porsche land.

[Loren]

Corrosion and bad crimps or chewed wires. All are possible as well as another sensor failure.

P1115 Oxygen Sensor Heating 1 Ahead of Catalytic Converter - Below Lower Limit

P1119 Oxygen Sensor Heating 2 Ahead of Catalytic Converter - Below Lower Limit

Possible causes:

- Contact resistance.

- Heating resistance too high.

- Open circuit in heating current circuits.

- Open circuit in H02S signal wire.

- Short to B+ (output stage cut off).

No such code as P1033 - perhaps it's P0133?

P0133 Signal Period for Oxygen Sensor Aging, Bank 1 – Above/Below Limit

Possible causes:

- Oxygen sensor

[phaphaphooey]

Corrosion and bad crimps or chewed wires. All are possible as well as another sensor failure.

P1115 Oxygen Sensor Heating 1 Ahead of Catalytic Converter - Below Lower Limit

P1119 Oxygen Sensor Heating 2 Ahead of Catalytic Converter - Below Lower Limit

Possible causes:

- Contact resistance.

- Heating resistance too high.

- Open circuit in heating current circuits.

- Open circuit in H02S signal wire.

- Short to B+ (output stage cut off).

No such code as P1033 - perhaps it's P0133?

P0133 Signal Period for Oxygen Sensor Aging, Bank 1 – Above/Below Limit

Possible causes:

- Oxygen sensor

Thanks for the reply Loren. I have gotten it down to just p1119. I have replaced that O2 sensor and the code came back today after clearing it last night with my OBD software. The O2 monitoring on the software shows that all sensors are working wonderfully. Quite frustrating.

[phaphaphooey]

Corrosion and bad crimps or chewed wires. All are possible as well as another sensor failure.

P1115 Oxygen Sensor Heating 1 Ahead of Catalytic Converter - Below Lower Limit

P1119 Oxygen Sensor Heating 2 Ahead of Catalytic Converter - Below Lower Limit

Possible causes:

- Contact resistance.

- Heating resistance too high.

- Open circuit in heating current circuits.

- Open circuit in H02S signal wire.

- Short to B+ (output stage cut off).

No such code as P1033 - perhaps it's P0133?

P0133 Signal Period for Oxygen Sensor Aging, Bank 1 – Above/Below Limit

Possible causes:

- Oxygen sensor

Thanks for the reply Loren. I have gotten it down to just p1119. I have replaced that O2 sensor and the code came back today after clearing it last night with my OBD software. The O2 monitoring on the software shows that all sensors are working wonderfully. Quite frustrating.

Just replaced the o2 again and although I had only started the car for 10 seconds to get it up on the ramps and hadn't driven it in over 24 hours, the o2 was hot when I took it off so the heater is obviously working. Quite frustrating.

[dr914jr]

I really like Loren's "chewed wire" idea. I think you should forget looking under the car and begin looking on top of the engine. I see that you first posted the issue in February. That's definitely prime rodent strike season. Even if that's not the issue you should always open up and inspect the engine compartment at least every six months. You might be surprised by what you find.