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 Control: Operation
The 808 (1300cc) and GLC (1300cc) manual transmission equipped models, have systems which operate to advance or retard ignition timing. Ignition timing is retarded whenever both accelerator switch and top gear detecting switch are on. Accelerator switch comes on when gas pedal is between idle position and 3/4 depressed (off after 3/4 depression). Top gear detecting switch is on in 1st, 2nd, 3rd, and reverse positions. Switch is off in 4th or 5th gears. Ignition timing is allowed to advance normally under all other driving conditions.
The 808 (1600cc) system operates by sensing vehicle speed and either retarding ignition timing or allowing it to advance. Ignition timing is retarded when vehicle speed is lower than 42 MPH and is allowed to advance at speed higher than 42 MPH (speed switch is off).
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- β’ You smell fuel, burning insulation, or see smoke.
- β’ Brakes feel soft, pull hard to one side, or make grinding noises.
- β’ The engine overheats, stalls repeatedly, or misfires under load.
- β’ You are missing required tools, torque specs, or safe lifting equipment.
- β’ You are not confident in the next step or safety outcome.
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