1997 Mazda Miata mileage: 98,000. My Miata started running bad as if it was missing I tested all the fuel injectors and fuel press and press regulator checked for spark on all four plugs looked good so I replaced my plugs and it ran great for a few miles then it started to get worse again as it was before. When I replaced the plugs, I noticed #1 and 3 were fouled. What could be doing this should I replace the plug wires and what else might I need to look at?
You may be fouling the spark plugs for number 1 and number 3 with oil due to possible broken rings or your engine may be just tired and using oil. You might try a hotter heat range on the spark plugs. We suggest doing a compression check and find out what is going on.