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Spark Plug Change

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Today I did a spark plug change on my car at 16450 miles. I had to order the plugs (Motorcraft Iridium CFSY-12) at my dealer since I was the first mechanic to ask for them. All of the stock plugs read perfect with no signs of running lean or too rich. There is a slight oil film on the threads but electrodes and porcelin were light tan. Some pics of the removed plugs.

Easy job, Remove PCV hoses and coil covers, 8mm socket to remove coil hold down screw, 5/8" spark plug socket and 10" of extension. Unbolt coil, pull up a little release tab on harness and pull off wiring, remove coil and clean seals and blow out spark plug well. Remove plug (do with engine cool so you don't pull out aluminum threads) thread in new plug by hand until seated and torque 10 ft/lbs (124 in/lbs). Little dielectric grease in coil boot and push back into well, tighten coil hold down screw to 7 ft/lbs. Replace coil lead (make sure it clicks. Do 8 times and replace covers, and PCV hoses. Test drive and enjoy! Most of you won't be doing this for at least 40000 miles but I like to see what's going on with the engine.


Small screw driver like Gary's post to get the red tab pushed back, or used finger.
Then a small screw driver to push down on the black release portion. It will click, then slide the connector off.
Tulsa, OK
Swapped in new plugs over the weekend. Easy process and didn't have too much trouble with the tabs. Good tips in here.

These are the stock plugs in my '12 GT with 18k miles and some track days. The car has been on e85 exclusively for almost 3 years now. All the straps are a consistent light brown. #8 has a little more residue higher up the threads than the others.


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