The 1990 Mazda Miata features a 1.6 liter engine and was the first generation of the car. Adjusting the timing on a Mazda Miata should not be done by anyone who does not have a good understanding of vehicles and their parts. An incorrect adjustment could lead to potential problems, including improper engine performance and oil leaks.
Start your Miata and let the engine warm up. Leave the vehicle running while you set the timing.
Open the diagnostics connector. It is located on the driver's side of the vehicle, in front of the air intake. It is on top of the engine in plain sight near the battery and is a small box.
Place the paper clip or the jumper in the "GND" and the "TEN" spots on the diagnostics connecter. The GND is the first box on the second row of boxes on the connector. The "TEN" is located in the second set of two boxes above the GND row. You will notice that the car begins to sound like it's slowing down. It should be at an idle level of 850. You can check the idle level using the tachometer on the dashboard of your Miata.
Connect your timing light to a 12-volt power source located behind the driver's side headlight. The power source is a blue plug shaped to fit the timing light cable.
Locate the Crank Angle Sensor at the rear of the passenger side valve cover, close to the firewall. The Crank Angle Sensor is circular and metal, and is located on the rear of the valve cover.
Loosen the locking bolt for the Crank Angle Sensor using the 12 millimeter socket. Loosen the bolt just enough to let you rotate the Crank Angle Sensor. The locking bolt for the Crank Angle Sensor is located on the lower side of the Crank Angle Sensor bracket, closest to the passenger side of the sensor.
Continue to turn the Crank Angle Sensor until the timing changes with the timing light. The timing light will be green when the timing is changed correctly. When the timing light turns green, tighten the lock bolt back into place.
Disconnect the timing light. Remove the paper clip or jumper from the diagnostics connector. Close the hood and turn the engine off.
