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Spark Plugs and Wires
Subaru Forester

How do you change spark plugs in a 1998 forester?


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Wiki User
August 27, 2008 4:48AM

Well.............................. I just finished the passenger side tonight and am ready to put Subaru engineers on a Wanted Poster. Passenger side spark plug removal First, you must remove the air cleaner housing. * Move the tube from the air cleaner and the intake on top of the engine by loosening the hose clamps at each end. It is still attached to a hose underneath but can be put out of the way. * Remove the top of the air cleaner and the filter. * Remove the two 12mm bolts at each side of the bottom. * The side of the bottom is rubber gasketed to the inside fender - just rotate slightly each way to loosen and pull off and put off to the side - there is still a wire attached. Now pull off the spark plug caps on the side of the engine. This is a Boxer engine which means the plugs are in a horizontal position on the sides. It is good to have a pair of spark plug pliers to do this as they are really difficult to remove. (spark plug pliers form a circle on the end when closed and are nice to grasp the caps with). The above was the real easy part. Now you will need a 3/8 drive socket wrench, a 2" extension and a 5/8 deep socket. I didn't use a spark plug socket with the rubber retainer inside - you can't remove the socket and extension with the spark plug in the socket - NO ROOM. It'd be nice to have a flexible shaft extension. My universal attachment wouldn't fit - angle to severe. #1 Plug (the easier of the two) Connect the extension and socket and feed it into the spark plug hole and over the spark plug. It is really deep inside. Now attach the wrench and remove the spark plug making sure you keep the tools level so as not to torque the plug side ways. Once the plug is real loose, unattach the wrench and hand loosen the plug with the extension because the wrench won't fit to remove the extension and socket attached. Remove the extension and socket and then spark plug. Put in the new plug reversing the steps. #2 Plug Basically the same process is used in smaller space. I had to finally call my wife (smaller hands) to do the finger lossening of the old plug and the finger tightening of the new plug. My hands, medium sized glove size, are too big to do this (minor arthritis) without pain. Again, where are those engineers. I may tackle the driver's side tomorrow. I took a quick glance and it seems I may have to remove at least the windshield washer tank. If the procedure is much different, I'll post the process here. Good Luck If any body has an easier process, this side of paying to have it done, please let me know.