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.
1991 Subaru XT StandardFACTORY OEM SERVICE PROCEDURE
Idle Speed & Ignition Timing
Ensure idle speed and ignition timing are set to specification. For adjustment procedures, see the ADJUSTMENTS article in the ENGINE PERFORMANCE Section.
IDLE SPEED SPECIFICATIONS
| Application | RPM | |
|---|---|---|
| 1.8L PFI | ||
| Non-Turbo | 600-800 | |
| Turbo | 700-900 | |
| 1.8L TBI | 500-600 | |
| 2.2L | ||
| Accessories Off | 600-800 | |
| Accessories On | 800-900 | |
| 2.7L | 650-850 | |
IGNITION TIMING (Degrees BTDC @ RPM)
| Application | Man. Trans. | Auto Trans. | |
|---|---|---|---|
| 1.8L | |||
| Non-Turbo | 20 @ 700 | 20 @ 700 | |
| Turbo | 20 @ 800 | 20 @ 800 | |
| 2.2L | |||
| Non-Turbo | 18-22 @ 700 | 12-28 @ 700 | |
| Turbo | 7-23 @ 700 | 7-23 @ 700 | |
| 2.7L | 20 @ 750 | 20 @ 750 | |
Factory Service Tools
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:
- • 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.