3 replies to this topic

[Rickorino]

I have a 2000 Cherokee with the 4.0 inline six and was wondering if there was a pcv valve. I do not see one in the valve cover. Am I missing something?

[ImperialCrown]

2.5L and 4.0L Jeeps used a 'metered orifice' and plastic hose instead of an actual valve. These were prone to plugging up with sludge. A clue was that the air filter would get an oil stain from blowby pushed into the air cleaner and oil would pool at the bottom of the air cleaner. The rich blowby mixture could also cause sags and hesitations. The valve cover itself could also restrict with deposits in this area at the rear.
I've tried clearing the plugged hose, but usually now just replace it.
You should see it pictured on your underhood vacuum hose routing label.

[Rickorino]

Thanks for the information. I will check that item and its plumbing.

[MoparNorm]

ImperialCrown, on January 8, 2012 at 05:24 am, said:

2.5L and 4.0L Jeeps used a 'metered orifice' and plastic hose instead of an actual valve. These were prone to plugging up with sludge. A clue was that the air filter would get an oil stain from blowby pushed into the air cleaner and oil would pool at the bottom of the air cleaner. The rich blowby mixture could also cause sags and hesitations. The valve cover itself could also restrict with deposits in this area at the rear.
I've tried clearing the plugged hose, but usually now just replace it.
You should see it pictured on your underhood vacuum hose routing label.

Plus 1. I believe the 'orifice' still originated from the valve cover? ...but I don't have a 4.0 that new to confirm.

Yep, it's still there on this 2000, 4.0