How to Replace Spark Plugs in a 1994 Chevrolet Van
- 1). Open up the doghouse engine compartment door on the interior of the van, located between the two front seats. Unclip the bottom clamps that connect the doghouse to the floor using your hands. Remove the doghouse entirely from the van.
- 2). Follow the spark plug wires from the distributor cap to their location on the engine. Pick the one closest to you and remove the plug wire by gripping it at the base and pulling it out while using a slight twisting motion.
- 3). Remove the spark plug using the 3/8-inch ratchet, extension and a spark plug socket. If you need to angle the socket into the hole, use the universal joint to do so.
- 4). Gap the replacement spark plug to the specifications listed in your owner's manual using the spark plug gapping tool. Then install the spark plug in the cylinder head using the ratchet and spark plug socket. Push the spark plug wire boot onto the spark plug until it pops into place.
- 5). Repeat steps 2 through 4 for the remaining five spark plugs in the engine. To access the front spark plugs, you may find it easier to pop the hood and reach inside, but that depends on your positioning inside the cab.
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