Where is the PCV valve on a 4 cylinder 1991 Jeep Wrangler?

The PCV valve on a 1991 Jeep Wrangler 4-cylinder (likely a 2.5L Renault engine) is typically located on the valve cover. It's a small, usually black, plastic or metal valve. It might be near the back or side of the valve cover, often with a hose connected to it leading to the intake manifold.

Because of the age and potential for variations due to modifications, it's best to consult a repair manual specific to your 1991 Jeep Wrangler 4-cylinder. A picture of your engine bay in a repair manual or online would greatly aid in identification. Searching online for "1991 Jeep Wrangler 2.5L engine diagram" should provide visual aids.