Intermittant check engine light

[Cletus S. Yokel]

I have a bizzare problem with my 2000 Legacy Outback Wagon. The check
engine light comes on sometimes for days, then goes out, sometimes for days,
then comes back on, etc. I had the codes checked and the indication was
"defective heater element, front 02 sensor. I replaced it...same ol' shit.
Same code. Sometimes CEL is on, sometimes it's off. Clear the codes, same
one comes back.

Ideas?

 

[someone]

I have a bizzare problem with my 2000 Legacy Outback Wagon. The check
engine light comes on sometimes for days, then goes out, sometimes for days,
then comes back on, etc. I had the codes checked and the indication was
"defective heater element, front 02 sensor. I replaced it...same ol' shit.
Same code. Sometimes CEL is on, sometimes it's off. Clear the codes, same
one comes back.

Ideas?

Sounds like a connection/wiring problem in the front O2 sensor CIRCUIT.
Somewhere between the ECM and the sensor.....

 

[Edward Hayes]

There are 3 O2 sensors. Any chance it's a different one than the one you
changed?

 

[TG]

could be the exhaust gaskets. TG

 

[Bud]

Get an ohmmeter and check the remaining O2 sensor heaters, one of them is
open.

 

[Cletus S. Yokel]

I still don't get why this would be intermitant. Also, the car runs
perfectly whether the CEL is on or not.

I was thinking along the lines that it may be a loose connection, but
considering the age of the car and the types of connectors involved, I doubt
that is the problem.