Changing plug makes car run rich?
Here's the scoop. I have a .15 CV-R which I broke in with the included A8 plug. After break-in and tuning thru 1/2 gallon, the plug gave up the goods. At the time, temps ran around 230-240, with a nice, thin trail of smoke. When the plug died, I swapped it with an O'Donnel plug my shop gave me. While the car fired up, I noticed the car bogged down and loaded up a bit if it idled more than 4 seconds and the smoke trail was now quite a bit thicker, indicating the mixture was now a bit rich. Sure enough, the temps were now around 215. Is this normal? Will I have to retune every time I switch brands of plugs? While I heard good things about the O'Donnel plugs, and there's only 2 kinds (1/8 and 1/10), I still have a few A8 plugs I can use.
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