1978 Dodge and Ram Colt Custom, Automatic TransFACTORY OEM SERVICE PROCEDURE

1974-75 Models

Check EGR valve for cracks or sticking. With engine at normal operating temperature, raise engine speed to 3000-3200 RPM. Disconnect vacuum hose to EGR valve. Diaphragm should lower. Reconnect vacuum hose to EGR valve. Diaphragm should rise. If not, replace EGR valve.

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.