Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Ignition Timing Reference Sensor
This sensor is located next to the engine RPM speed sensor. It detects the rotation of a pin located 60 degrees BTDC. This sensor sends a signal to the ECU when TDC occurs for number one and number 4 cylinder. The Hall Effect switch, located in the distributor, produces only one signal for each revolution of the distributor. This signal occurs just before TDC of number one cylinder. This signal is used to determine which signal from the ignition timing reference sensor is the actual TDC signal for number one cylinder. DO NOT rotate distributor to set base timing.
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.