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Have a 94 NA Miata with a new PNP MS installed. During a wide open run, RPM will fall to 0 and come right back intermittently. Tried a different CAS with just about the same results. Hooked a scope up and the signal is pretty dirty, but the odd thing is that the crank signal goes from 0 to 13v and the cam signal goes from 0 to 5v. Anyone ever see this before? When I check voltages at ECU with CAS disconnected I get 4.8v on 2G(Y/L) and and 10.8v on 2E(W). 10.8v is what battery voltage was at the time.