Where are the two knock sensors located on a 2002 GMC 2500HD with a 6.0 engine. Which sensor is classified as number one and number two.

knock sensor job is to smooth out the engine from knocking or pinging. meaning one of cylinders is not running well

Knock sensors located under the in-take, in-take will have to be remove to replace sensors.

There's two knock sensor's, and there under the in-take, on top og the engine, when the knock sensor detects a knock on the engine block, it will send a signal to your compute to adjust the engine timing.

If all connections are good "dry, tight, no corrosion" then yes. It should be a defective sensor. These sensors are piezo sensors and create a voltage when sensing a knock. A bank refers to a side on a V style engine, 2 refers to the rear sensor on your bank 2. Bank 1 should be the side with cylinder #1 which should be the cylinder closest to you on one of the sides. So your looking for the rear sensor on the opposite side.

Here's a location pic...

Knock sensors as a rule of thumb are positioned right beside a piston on the the block. It should be on the opposite side of the exhaust system. A knock sensor is actually a sensitive microphone or listening device. It listens to a piston performance under load. If it hears a knocking or pinging sound it will ****** the ignition timing and advance it again when condition changes. It would have a securing bolt in the middle which torqued to a certain spec and a single wire harness.

remove the intake manifold ,remove radiator ,remove radiator intake and outake housing, remove fan ,remove all belts: power steering, alternator and if you have a/c, remove harmonic balancer ,remove timing belt covers, remove timing belt remove intake housinng once you have remove all the above, your freaken engine will look naked, you can see the location of the knock sensor is locate in the engine valley hope this helps u might wnat to google knock sensor so u knoe what it looks like

The knock sensors are under the intake plenum ( the plastic part ). There are 2 sensors.

Not on this engine. Timing and fuel are already optimized right up to the point of detonation and then trimmed with the knock sensor. Only hardware will help here and it's really not worth the result.

I just replaced mine on an '04 8.1 vortec. Ez fix. Pd $33 at Rockauto. The sensor in located on the front of the engine &slightly toward the drivers side. Unplug the electrical connector and remove the single nut (10mm). Evenly pull the sensor out from the block. Only use the force needed. Don't yank. Place a oil on the new sensors o ring & reinstall.