1992 Jaguar XJS 2D ConvertibleFACTORY OEM SERVICE PROCEDURE

Idle Speed & Mixture: Notes

NOTE: Mixture adjustment is NOT a part of normal tune-up procedure and should not be performed unless mixture control unit is replaced or vehicle fails emissions testing.

Idle speed and mixture is electronically controlled by the ECU and various engine sensors. Adjustment should not be required. If idle speed is not within specifications, ensure throttle plate is adjusted correctly. See THROTTLE PLATE ADJUSTMENT  .

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.