PCV Valve Test

NOTE: If vehicle is driven under dusty conditions, replace filter element as necessary. Inspect and replace any hoses that show signs of damage or plugged condition.

1. Install a PCV valve known to be good in the crankcase ventilation system.
2. Start engine and compare engine idle condition to the prior idle condition.
- If the idle condition proves satisfactory, replace the PCV valve and clean hoses, fittings, etc.
- If the loping or rough idle condition remains when the good PCV valve is installed, the crankcase ventilation system is not at fault--and further diagnosis will have to be made to find the cause of the malfunction.