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.
Description & Operation
The crankcase ventilation system is designed to control the flow of crankcase gas and vapors into the intake manifold to be burned by the engine rather than being discharge into the atmosphere. System is a closed type and consists of a positive crankcase ventilation (PCV) valve, 3-way joint, and connecting hoses.
Under normal driving conditions, intake manifold vacuum is high and the PCV valve opening is limited. The amount of blow-by gas drawn into the intake manifold is small.
Under heavy acceleration or high-speed driving, intake manifold vacuum decreases and the PCV valve is wide open due to its spring force. In this case, a large amount of blow-by gas is drawn into the intake manifold.
Use the Manual With the Right Hardware
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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.