• Hi, Jon: Terrific website! I just bought some new Bosch sparkplugs to install myself, since the access to the plugs is so good.  However, the plug wires seem to be stuck or clamped-on.  Can you help?       Joe Pfister

• This is a very common problem. The correct plug for the 6cyl on the 91 300E should be a H9DCO. What happens is the little spring inside the wire end corrodes to the plug. I use a needle nose vise-grip and clamp down on the metal part of the wire end, like from underneath then use the engine head as the lever and pop them out. Remember not to pull on the wire or the rubber section of the end, just on the metal part. Once you have mastered the art of removing stuck wire ends make sure you put some kind of lubricant in the spark plug wire end. Not WD40 but something like trans fluid. Make sure you grease the threads on the plugs as well. JON

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