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.
PCV System - Diesel: Description
Positive crankcase ventilation system is designed to prevent contaminating hydrocarbons, created in the crankcase, from escaping into the atmosphere.
Ford use a closed type system, designed to force engine generated blow-by back into the intake manifold. It then returns, mixed with fresh air, to the combustion chambers.
Oil separator separates oil particles from blow-by gas and returns it oil pan through a check valve which keeps oil from flowing out of pan. Oil separator prevents the formation of carbon deposits produced by mixture of EGR gas and oil mist contained in the blow-by gases.
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.