They are listed as PCV valves, Positive Crankcase Ventilation. I am just replacing the front one with a breather since I put a different air intake on mine.

 

rear



front

 

Good to know.

 

Would have saved me a lot of time and a pretty penny to have known! But Im gonna switch to rotella T5 oil and new felpro gaskets while I have it apart!

 

Yeah some parts stores carry them as "PCV" because their computer only has one category. Ventilation of the crankcase in a 4.0L is a draw-through continuous system referred to as CCV. There are no valves, the rear elbow is a metered orifice. The little hole is exactly what it looks like. PCV systems are pressurized and do not take in fresh air. The valve releases the pressure and prevents the formation of a vacuum.

The front elbow is nothing special, it just needs to be filtered air. Since it's used by the engine, and it mixes directly with the engine oil, it should be filtered to engine standards.

 

Thanks for the info! Yea the front elbow was just completely open, Im using a spectre oil breather, like was on the old engines

 

If you start to notice oil coming out of that, make yourself a little catch can to keep it from getting all over the engine compartment. Shouldn't have an issue with the newer models' steel valve covers, but I know it was a problem with the earlier aluminum covers and the longer inner flukes.

 

I might have missed it but did you clean out the fitting at the intake manifold? All that residue ends up there. If its clogged then the engine can't inhale the vapours

 

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I have a 2007 Grand Cherokee. 3.7L This code keeps coming up, I've had different mechanics look at/ work on my Jeep. At Idle my Jeep Idles at 630 rpm. Is this High or normal? Am at a loss as to what do next...

 

Yes, I did clean it out. I even ran a new line from fitting to intake.

 

Based on a semi-quick search, the consensus is between 600-650 RPM. What code are you seeing?

(source: http://www.jeepkj.com/forum/f196/idle-500-rpm-35685/ )

 

Thanks

 

So, I bought a 93 Grand Cherokee with the L6 engine, automatic transmission. The folks I bought it from did a number on the wiring. Just looking for the wiring diagrams for the vehicle. The interior electrical is messed up, as well as the tail lights and signals. Any help would be cool.

 

I'm replacing my oil pressure sensor (96 xj), but I've noticed the connector plug is damaged, the single-wire one. I can find the sensor anywhere, but nobody seems to carry the plug... any source suggestions? I have found some places tha carry a thing they are calling a connector for this but it can't be, it has two wires....