Ignition Timing: Adjustments

1985 Buick Century V6-231 3.8LSECTION Adjustments
Always follow the Emission Control Information Label procedures when adjusting timing.

Set timing at low idle and Before Top Dead Center, unless otherwise specified. Disconnect and plug distributor vacuum hose at distributor.
1981-90 all carburetted with C-3 System, disconnect 4-wire connector at distributor. If "Check Engine" light comes on during procedure, remove ECM fuse to clear.
1982-86 1.8L (112) FI, 2.5L (151) engines, ground diagnostic connector.
1983-86 2.0L (122) FI, 2.8L (173) FI, disconnect EST bypass connector (tan/black wire).
All W/O distributor not adjustable.



RENDER: 1.0x

NO RELATED

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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.