Trapped Vacuum Spark

1985 Chevrolet Chevy Van G30, 5.7 M, 400/M40SECTION Trapped Vacuum Spark

Thermal vacuum switch (TVS) is mounted in cylinder head and used to sense engine coolant temperature. Vacuum check valve is mounted between manifold vacuum, distributor and thermal vacuum switch. System maintains high vacuum levels to distributor during cold engine operation and cold engine acceleration.

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:

  • 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.