Honda - Accord Prelude 1996 2000

Positive Crankcase Ventilation (PCV) Valve


The Positive Crankcase Ventilation (PCV) valve is part of a system, which is designed to protect the atmosphere from harmful engine blow-by gas vapors. Blow-by gas from the crankcase, as well as fumes from crankcase oil, are diverted into the combustion chamber where they are burned during engine operation. Proper operation of this system is necessary for optimal engine performance, and decreases the amount of harmful vapors released into the atmosphere.

All Honda Accord and Prelude models are equipped with a Positive Crankcase Ventilation (PCV) system in which blow-by gas is returned to the combustion chamber through the air intake system.

For more information on the PCV system, please refer to Section 4 of this guide.

The PCV valve should be checked according to the manufacturer's recommendations. On 1996 models with the 2.2L engine, Honda recommends checking the valve every 60,000 miles (96,000 km) or 4 years, whichever occurs first. Although there is not an official manufacturer's recommendation for the remaining model years, checking the PCV valve is a simple task, and most professionals would recommend checking the valve during tune-ups. Two consequences of a failed PCV valve are the possibility of an intake vacuum leak which could cause erratic engine running conditions, or the inability of the crankcase to adequately vent combustion blow-by gases causing potential oil leaks.


The PCV valve is mounted in a rubber grommet, which is seated in the intake manifold and has a hose connected to it from the crankcase breather chamber.

  1. Before removing the valve, thoroughly clean the area surrounding the valve.
  3. Remove the valve by carefully lifting the valve away from the sealing grommet and the manifold.
  5. Once the valve is removed check for loose, disconnected or deteriorated lines or hoses and replace if necessary. Make sure the hoses are clean and free of debris. Clean them with a suitable solvent, if necessary.

Click image to see an enlarged view

Fig. View of the PCV valve (A) and related hoses (B)

To install:

  1. To install the PCV valve, coat the mounting grommet with a light coating of engine oil, then press the valve into the grommet.
  3. Reinstall the vacuum line and clamp.