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.

1990 Pontiac LeMans BaseFACTORY OEM SERVICE PROCEDURE

Spark Plugs

SPARK PLUG TYPE

Application	AC
All Models	R45XLS

SPARK PLUG SPECIFICATIONS

Application	Gap In. (mm)	Torque Ft. Lbs. (N.m)
All Models	.045 (1.1)	15 (20)

Fig 1: Firing Order & Distributor Rotation

BASE IGNITION TIMING (Degrees BTDC @ RPM)

Application

Specification

1.6L ⁽¹⁾

⁽²⁾⁽³⁾⁽⁴⁾ 8 @ Idle

2.0L ⁽¹⁾

⁽²⁾⁽³⁾ 8 @ Idle

⁽¹⁾	Ground ALDL test connector.

⁽²⁾	Align timing marks to obtain specified degrees.

⁽³⁾	Idle speed as specified on emission decal.

⁽⁴⁾	If using the magnetic pick-up timing light, set timing to 10 degrees BTDC. See Fig 2 .

NOTE: A magnetic pick-up timing light may be used on 1.6L engine.

Factory Service Tools

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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.