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O2 Sensors

I need step by step instructions on how to change out my o2 sensor on my 1986 El Camino. I’ve looked and looked and I caint find it nowhere.

Which can’t you find? The sensors, or instructions? Changing them is pretty simple, unscrew the old one and screw in the new one, with high-temp anti-seize of course.

Are you saying you cannot find the sensor? Have you checked everywhere from the exhaust manifold to the converter?

By the way, this may need penetrating lubricant, patience, leverage perhaps some impact, and maybe some heat, all in abundance. They do tend to weld themselves in with corrosion over the years.

Go to this website http://www.autozone.com/autozone/, and at the top of the page click on My Zone. Register, and you can look up the procedure, location, and tools required to replace the O2 sensor.

Tester

The oxygen sensor is in the exhaust manifold. After 20+ years, it will be extremely difficult to remove.
Run the engine until the exhaust gets hot; or, use a propane torch (available at home repair centers) on the area around the oxygen sensor. Use a 7/8" box end wrench. Place your foot on the box end wrench, and push. Push, some more.
When that doesn’t work, cut the wires from the oxygen sensor, use a 6-point, deep-well, 7/8" socket and breaker bar, and push. And, push. Come on, PUSH harder than that! It will be tight, all the way out. Take a break. Have a beer. Resume.

Added: The special socket, with the slot for the wires, is likely to spread, and slip, when a lot of force is applied to it. That’s why I say to cut the wires and use a deepwell 6-point socket with a 1/2" drive; or, a 3/4" drive, if you can get one.

As everyone says, after a couple of decades, that O2 sensor will probably have become one with the car. They make special half inch drive sockets with a slot for the wires especially for Oxygen sensor removal. You can get one at most parts stores for not all that much money. The nuclear option – which you may need – consists of an O2 sensor socket, a sturdy breaker bar, and a three foot pipe to extend the breaker bar. Something will give if you apply enough force. Be careful not to have portions of your anatomy between the pipe and any solid object when something does finally break.

A better and potentially less damaging option if ordinary tools fail is to pay someone with a heavy duty impact wrench to get the O2 sensor loose. That assumes that the O2 sensor can be gotten at with an impact wrench.

you might want to try some penetrating oil before removing it