Firing order 84 madza rx7
If your tach does not work that is a symptom. Of course a timing light is most useful. If not you can coil wires (swap with known good wire) ; check ignitor,(swap trail/lead ignitor plugs at distributor) coil, check with ohm meter.
Trailing ignitors are very common failures, especially when either jump starting or being jump started when a battery is stone dead. What happens is there can be a huge power spike through the ignition system damaging the electronics in the ignitor. 90% of trailing ignitor failures happen during a jump start procedure.
At this age though, wires and coils can be suspect. My recommendation for ignition parts, Mazda Mitsubishi Cap/rotor and NGK wires and plugs. They are good enough for Mazda factory race teams and I have been using them since 72 with no ignition related failures in racing or all the street vehicles that have been maintained. Most critical is the fit of the rotor, it should be very hard to install, very tight fit. If loose the rotors have a tendency to rotate and move causing changes in timing and at worse damaging the cap and rotor.
Apr 20, 2013 |
1984 Mazda RX-7