How to Replace Corvette O2 Sensors

by Richard Rowe

Oxygen sensors (also known as "O2 sensors") are essentially temperature probes. Air/fuel ratio has a direct relationship to exhaust gas temperature: A fuel-rich ratio will make the exhaust colder, and a fuel-lean mixture will make it hotter. The vehicle's computer system extrapolates from exhaust gas temperature to make minor changes in the fuel injection and ignition duty cycle to optimize for power, fuel economy and engine longevity. Chevrolet Corvettes produced before 1996 have only one O2 sensor on the exhaust manifold or in the pipe connected to it. Corvettes produced in or after 1996 use one O2 sensor in the exhaust manifold and another after the converter.

Raise the front of the car with a floor jack, and secure it with jack stands. You should only need to lift the car by about six inches to access the O2 sensors.

Identify the first O2 sensor, which will be either on the drivers' side exhaust manifold or about three inches away from it on the exhaust pipe. Newer Corvettes have an O2 sensor on each manifold. Identify the second O2 sensor on the exhaust pipe just past your catalytic converter.

Unplug the wiring harness connector from the O2 sensor you wish to replace. You may need to use a flat-head screwdriver to release the locking tab on the harness.

Slip your specialized O2 sensor removal socket (available at your local auto parts store) over the O2 sensor, allowing the wires in the top of the O2 sensor to slip out of the slot in the side of your socket. You can use an open-ended wrench to remove the after-cat sensor.

Connect your O2 sensor to your ratchet using whatever arrangement of extensions and U-joints that you need. For instance, to get around the front crossmember you may need to use a socket connected to a U-joint, connected to a three-inch extension, connected to another U-joint and then a six-inch extension. Turn the ratchet or wrench counterclockwise to remove the O2 sensor. This might take some elbow grease if your car has a lot of miles on it.

Put a pencil eraser-sized dab of anti-seize compound on the threads of your new O2 sensor. You'll thank yourself for it when you need to replace the O2 sensor again in 10 years or so.

Screw the new O2 sensor into the hole where your old one came out, turning it as tight as you can with your fingers. Tighten your O2 sensors to at least 30 foot pounds using your wrench. In practical terms, it's almost impossible to strip an O2 sensor bung with basic hand tools, so just grab a handful of wrench and pull.

Plug the wiring harness back into the O2 sensor. GM harnesses only go on one way, so it's hard to make a mistake here.

Items you will need

About the Author

Richard Rowe has been writing professionally since 2007, specializing in automotive topics. He has worked as a tractor-trailer driver and mechanic, a rigger at a fire engine factory and as a race-car driver and builder. Rowe studied engineering, philosophy and American literature at Central Florida Community College.

Photo Credits

  • photo_camera corvettes image by michael langley from Fotolia.com