I put some g-power NGK plugs in my 94 Corolla and had a rough idle recently in the cold; I've read platinum plugs might not be good for older cars requiring copper plugs, so I got a set of v-power Ngks that the factory specs. Plugs 2, 3, and 4 came out fine and the new ones threaded in great and were installed easily. Hand tight to thread them in, then 1/2 turn with the ratchet to crush the washer. However, on cylinder 1, when I try and put a fresh plug in that hasn't had the washer crushed yet, when I hand tighten the plug in, it threads in fine, but when I try and do the 1/2 turn with the ratchet, there is a ton of resistance like the bottom most threads are carboned up. I'm willing to bet if I used a torque wrench at 18 pounds, it wouldn't be enough to fully crush the washer. I've tried 3 plugs in cylinder 1 and they all do this; it doesn't feel like the threads are stripped at all. After trying to install it with moderate force on the ratchet, the gasket isn't crush hardly at all.
Anyone ever have this problem? Do I chase the threads with a thread chaser and hope I don't screw it up? Spray carbon cleaner in the hole? I've changed the plugs on this car probably 10 times since I've had it and never had this issue. Thanks!
Anyone ever have this problem? Do I chase the threads with a thread chaser and hope I don't screw it up? Spray carbon cleaner in the hole? I've changed the plugs on this car probably 10 times since I've had it and never had this issue. Thanks!
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