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: Specifications
This is the exact OEM manual section for the path above. Use the breadcrumb to move up or down the tree until you reach the precise year, make, model, and subsystem you need.
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Engine Control Module Scan Tool Data Parameters
Parameter: Spark
18-24 Degrees
The scan tool displays a range of -64 to +64°. The scan tool displays the amount of degrees the PCM commands. The PCM computes the desired spark advance using the following: (1) ECT, (2) engine speed (RPM), (3) load, (4) vehicle speed. The PCM adjusts the timing.
A negative (-) value indicates degrees before top dead center (BTDC) or spark advance; a positive value indicates degrees after top dead center (ATDC) or spark retard.
Engine Control Module Scan Tool Output Controls
Output Control: Spark Control
Enables or disables idle spark command. When commanded ON, the idle spark will be controlled to 13 degrees before top dead center. The normal commanded state is OFF.
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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.