HELP, Intermittant CEL and Codes

[dr_karlb]

Can you knowlegable guys help me.

I have an intermittant CEL issue.

The codes are P0139 and P1117. The readed i had didnt have useful descriptions.

The CEL started coming on about 3 weeks ago, always at the same place on my drive home in the evening

(about 5 minutes from work, on an approx 50mph expressway)

It would stay on for a day or so and then not show up again for 2-4 days, then the same deal, perhaps 4 times now.

I only just got find a code reader while i still had the CEL on to read the codes

Any advice ?

BTW its a 2001 Carrera4 Cab, 14,000 miles, minor service and MAF replaced approx 6-months ago. No mods (well PSE mufflers installed)

Thanks in advance

[Loren]

Check the wiring on that O2 sensor and/or clean the electrical connections (while it is cool). If that does not cure it you will need a new O2 sensor.

Those codes indicate the heater circuit is failing in that O2 sensor - not that uncommon.

[dr_karlb]

Check the wiring on that O2 sensor and/or clean the electrical connections (while it is cool). If that does not cure it you will need a new O2 sensor.

Those codes indicate the heater circuit is failing in that O2 sensor - not that uncommon.

One other quick thing...

Which sensor is P0139 ? Drivers side or passenger side.

Is it the sensor running along the pipe just below the rear bumper ?

Thanks

[Loren]

Bank 1 is Cylinders 1 - 3 so that would be the left side (driver's side for LHD cars).

There are two O2 sensors for each bank of the engine - one before the cat and one after the cat. You want to inspect/replace the one after the cat (muffler side) on the left side of the engine.