If it has the 5'3L or the 6.0L engine , the intake manifold must be removed to gain access to the knock sensors (2 of them). Some mechanical experience and the proper tools along with the shop manual would be recommended.
On a 2002 4.3, the knock sensor is located behind the driver side cylinder head. The knock sensor is very hard to reach.
It is under the intake manifold. Darn hard to get to and expensive to change.
Again, not difficult. But, one of those jobs when you should have a repair manual handy. The knock sensor lies beneath the intake manifold. Components that you would not think about must be removed and the torque sequences for reassembly are very specific.
it's hard! you have 2 knock sensor under you plastic intake. than you take your intake off you will see a wire with two black top about 1 1/2 to 2 in. pop those off and there there they are. it is a good idea to replace them both and get you a new wire from the dealer fro the knock sensor. i hate to hear you have to do it twice just cause you did not want to buy the knock sensor wire. and if you careful you can save the intake gasket. be sure and buy all you parts first. 2 knock sensors , knock sensor wire and intake gasket. if you don't used it take it back .
it sits just below the intake manifold...hard to get at .
Under the intake manifold above the fuel filter. Hard to see, hard to reach.
Knock sensors detect detonation ( knocking ) by reacting to the ping by retarding the ignition timing so you will need a timing light for this. connect the timing light and locate the knock sensor, ( many are on the intake manifold ) now use a metal object to tap ( not too hard and not on the sensor itself ) on the intake manifold ( light tapping should suffice ), if the sensor is functioning you will see the timing retard. If the timing does not retard you will need to check voltage across the terminals of the knock sensor connector.
On the back of the engine block. 3 bolts to take it off, easy to do but hard to reach.
Back of the engine block. 3 bolts to release and ridiculously hard to reach.
Couldn't be easier. Once you locate the knock sensor below and behind the intake manifold, it is held on with one screw through the middle and connected to the wiring harness by one plug. Finding it is the hard part. --Ken
you will have to remove intake and you will see it underneath two coolant lines. can be done. time cosuming and a lot to take apart. ON THE ENGINE HEAD AND IT IS VERY HARD TO BE CHANGED.
behind the engine,in front of the transmission, about half way up the side of the block, its very hard to see its near the knock sensor.