If you take the engine cover off, down the left side of the block (passenger side of the car) are four coil packs. You remove the coil packs and the plugs are inside the block. You'll need an extension to remove them.
Usually the cylinder head holds the spark plugs.
In the cylinder head.
The spark plugs are located on the side of the engine, near the bottom. A four-cylinder engine will have two spark plugs on each side. A six-cylinder engine will have three spark plugs on each side.
In the cylinder head .
Between the cylinder head the spark plug wire.
The cylinder head is located on top of the engine. The spark plugs thread into the cylinder head(s).....
The knock sensor on a Passat is located on the side of the engine. It is just below the number two cylinder spark plug.
Screwed into the cylinder head.
It is located over the cylinder head.
There would be six spark plugs for a six cylinder engine. One for each cylinder. Unless it is a diesel, then there are no spark plugs.
You can find the spark plugs for your 2002 Nissan Pathfinder on each side of the engine. The spark plugs will be near the top of the engine. A six-cylinder engine will have three spark plugs on each side.
They are located in the cylinder heads. Just follow the wires and that will lead you to them