They are screwed into the exhaust system / pipes. Unscrew them and replace.
you have to remove the intake, and there are 2 knock sensors.
Check conections on the o2 sensors . Replace the 02 sensor.
In The Seats.
There are approximately 2 oxygen sensors on a 2005 Chevrolet Astro van. The oxygen sensors can be purchased at stores such as NAPA.
2002 Chevrolet Tahoe has two oxygen sensors How do I check them ?
where is the oxygen sensor located on a 1997 Chevrolet lumina
2005 Chevrolet Classic FWD
Two sensors, and replace them.
There are two knock sensors on your engine, and they are underneath the intake manifold. You will have to remove the intake to get to the sensors.
There are 4 sensors on the 1995 Chevrolet Blazer. The 2 front for the Disc Brakes is behind the rotors on the hub. The inside hub has gears and the sensors are above them. On the rear, where you have Drum Brakes, the sensors are on the back of the Drum Brake Assembly, next to the bleeder screws.
Without knowing what sensors you are trying to replace, there is no answer. Please re ask question about a specific sensor.
abs sensors are at the axle hub