The owner of a 2003-10 Pontiac Vibe may come into your store complaining that the check engine light and/or VSC lamp comes on intermittently. With a little investigation, you may find trouble code P0607 and/or P0138 logged in the PCM.
According to GM, the problem usually surfaces in high ambient temperatures with the A/C system on, and most likely is due to water entering the pre-cat O2 sensor's electrical connector.
A clogged evaporator drain is the true villain. Drying the connector and clearing the drain should turn off the lamp(s) in a hurry.
Start the repair off by removing the small side panel cover just to the right of the accelerator pedal. Now pull the carpeting back to access the O2 sensor connector.
Separate the connector halves, dry the terminals with compressed air, fill both connector halves with silicone grease, then reconnect the two halves.
To complete this portion of the repair, pull the carpeting back into position and reinstall the side panel cover.
Now turn your attention to the evaporator drain. Begin by putting the vehicle on a lift.
Locate the drain hose, then use a coat hanger or compressed air to clear the blockage.
To complete the fix, lower the vehicle, start the engine, turn the A/C on and make sure condensation flows freely from the drain hose.
"Factory Fixes" is written by Jim DePalma, a 30-year veteran of the auto repair business who has served stints as a service manager, parts manager and ASE-certified technician. His column provides vehicle manufacturers' authentic factory technical service bulletins (TSBs) that have been condensed for easier reading. Mr. DePalma advises that techs always check with a dealer or repair information system for the latest revisions before starting to work on a vehicle. He can be reached via e-mail at [email protected].