So, I am new to the Miata. Just bought my first one about 2 months ago. It is a 93 with a lot of miles (167,000) but I plan on a new motor eventually anyway. So I decide to perhaps advance the timing a few degrees and go to miata.net for some research. They happen to have a diagram up of the engine,
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includes plug wire set up. I notice that it is different for the1.6L & 1.8L engines but don't think much about it. I go back outsideand happen to notice that my plug wires (NGK) are not all reaching theplug appropriate to their length. I go back and look at theaforementioned diagram and sure enough someone has put my wires in1.8L and NOT 1.6L configuration!! I would have expected such a mix upto cause all sorts of obvious problems (check engine light, rough idleetc...). Now this car had seemed underpowered and I had noticed somepeculiar hesitation and slightly askew rev tendencies, but nothing soextreme that I could not attribute it to simply being a high mileagecar. After putting the wires back in their proper order the car issmoother and seems to have picked up 10-20hp. I spoke to the garage that has done all the work on it since it had
35,000 miles on it and they cannot give me any answers as to why it did not run more poorly. In addition their records (which I had previously gotten a copy of for my own) showed that they had never replaced the plug wires, though they have done several sets of plugs.
I would love to know if anyone has ever heard of this and what kind of lasting damage, if any, it is possible this could do to the car.
Thank you,
Damien