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If your vehicle is equipped with spark plug wires (as opposed to a coil-on-plug system), the wires should be replaced at the same time.Plugs should always be promptly replaced per the manufacturer maintenance schedule even if they appear to be working perfectly.Consider earlier than required inspection and tune-up if you operate the car in severe conditions. High-speed driving may accelerate spark plug wear.Mine hadn’t loosened up at all, but if they have, this gives you an opportunity to get them tight again before they blow out.When having spark plugs replaced keep in mind: Follow-UpĪfter a few thousand miles or the next oil change, it’s a good idea to check the torque on the plugs. That bolt can just be made snug I don’t know if there’s a torque setting. I’m lazy and often skip this step.įinally, stick the COP bolt back through the COP and cinch it down. Use a torque wrench.īefore reinstalling the boot, you can put dielectric grease around the bottom of the boot to help seal the plug. I’ll again warn against just “snugging it up” on this particular engine. The actual spec range is 11-15, but anecdotal reports suggest 14 is a good value that keeps the plugs from backing out but doesn’t strip the threads in the head. Then, once it’s definitely threading in, grab the torque wrench and torque it to 168in-lbs (which is 14ft-lbs). Instead, make sure the plug is threading in properly by finger tightening the extension directly. If you buy iridium plugs, you cannot gap them or you will damage the electrode.ĭrop the plug into the hole using the magnetic socket and an extension. I checked one or two, confirmed they were correct, and installed the batch. You can gap the plugs again with a plug gap tool, assuming you bought copper plugs like I did. Still, I think I’d rather have my plugs back out on their own than be stuck in the engine. This is somewhat controversial, as some people think it will increase the chances that the plug will loosen up and shoot out. The new plugs should have a dab of antiseize put on them. Even an inaccurate click-type wrench is better than guessing and hand tightening for this procedure. I use my click-type wrenches for anything over 15-20 lb-ft or so. In general, beam-style is more accurate and cheaper than click-style, so I prefer it for small torque value applications like this. That’s still on my to-buy list, so I used a Craftsman 3/8″ Beam-style foot-pounds torque wrench instead. Ideally, you’d use an inch-pounds torque wrench if you have one. Guessing at how tight you’re getting the plugs will lead to them shooting out. It is also helpful to have a long 3/8″ extension. I cut a hole in the floorboard so I can push the gas pedal down more. Good luck and lets see some pics when you have a chance. If you installed a coil with more voltage, or plug wire with lower resistance or an MSD box. A 3/8″ u-joint socket is also helpful on this car, as it can be tough to get the socket into the plug wells. The sticker generally reads: Spark Plug Gap. They seem to grip the socket well and yet let go more easily once the socket is removed.
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A lot of spark plug sockets have a rubber o-ring to grip the top of the spark plug, but I prefer the magnetic ones like I linked. Other Items Requiredīesides plugs, you need some anti-seize, a basic socket socket, and a spark plug socket. Supposedly, Motorcraft plugs are less likely to shoot out, but this is probably unfounded internet rumor. You need eight spark plugs for a v8, of course. At the time I ordered it, $2.95 bought you two packs of four. I went with Motorcraft SP-493 plugs, which are the Ford house brand.