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.
Relief/Diverter Valve
The relief valve maintains a constant air pump pressure of 3.8-5.7 psi (.27-.40 kg/cm2 ). Excess pressure is vented to atmosphere. The diverter valve switches air injection from the exhaust manifold to atmosphere during deceleration. This reduces backfiring. When intake manifold vacuum rises above 8 in. Hg, the diverter valve closes and diverts air pressure. A calibrated air bleed in the diverter valve gradually opens valve and air injection is resumed.
NO RELATED
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.