1986 Mitsubishi Mirage BaseFACTORY OEM SERVICE PROCEDURE

Jet Air System: Description

The Jet Air System uses an additional valve at the top of each combustion chamber to inject a high velocity stream of air during low throttle operation. On intake stroke, air rushes out of jet valve opening into gases around spark plug and produces a strong swirl action in the combustion chamber. This promotes high combustion efficiency and results in lower exhaust emissions.

The jet valve is operated by an extension of the intake valve rocker arm. The valve assembly consists of a jet valve, jet body and spring. The assembly is screwed into the jet piece, which is press-fitted in the cylinder head with the jet opening toward spark plug.

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:

  • 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.