"The other thing I considered is to use a pry bar to pull on the plugs. The concern there is I would be potentially using a large unknown amount of force on the plug, which goes back to the fear of breaking one.[/QUOTE]"


I don't think the pry bar approach would be a wise thing to do. I know in my case, I had two plugs that were unscrewed, but would not come out. I was able to use a deep socket, and just kept turning them back and forth using plenty of PB blaster. I was able to move the plugs about one half inch in each direction, but after about a day of soaking and moving the plugs they finally came out in one piece. By using the deep socket, each time I moved the plug, I would apply a slight upward pressure and stayed within the 40 to 45 NM. Worked on a lot of cars in my life, but this glow plug job gave me more white hairs than any other job I ever did. Good luck

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96 E300d