Ok, can someone verify where the PVC valve is on the engine. Also, if I am correct in what I think is the PVC valve, why would just have a negative pressure on it. I am in the process of installing a fuel atomizer and it should have a postive pressure from the PVC valve, then into the atomizer, then back out to the intake manifold.
My understanding of the PVC valve is to recycle the unused fumes in the valve cover area, and send them back into the intake. I placed a plastic bag on the PVC connection and it sucked it in, and did not expand it.

Thanks,

 

I think the PCV is located in front of the throttle body under the "HEMI" cover. Also if you look at the decal on the underside of the hood it will give you a sketch as to where it is as well as the appropriate spark plug gap and some other stuff. It will also be negative pressure as it will form a seal with your thumb if you place your thumb over it with the engine running. I don't know about the fuel atomizer thing or a positive pressure at the PCV. Perhaps someone else with more knowledge can shed some light.

 

Well the way engines should work is that there is a positive pressure coming off the engine. This positive pressure is the unburned fumes that come off the engine that are in the valve cover area. So this is why I do not understand the negative pressure. Is the engine to thirsty for air it is resucking the vapors back through the valves.

 

PCV line will have vacumm there all the time. Its job is to keep negative crankcase presssure. Doing this will recycle the vapors trapped inside the engine and help gaskets from leaking as often. The hose going to the PCV will go to direct manifold vacumm.

 

5.7L V-8
The 5.7L V-8 engine is equipped with a closed crankcase ventilation system and a Positive Crankcase Ventilation (PCV) valve.

This system consists of:

a PCV valve mounted into the top of the intake manifold, located to the right / rear of the throttle body (LOCATION 5.7L PCV VALVE). The PCV valve is sealed to the intake manifold with 2 o-rings (5.7L PCV VALVE).
passages in the intake manifold.
tubes and hoses to connect the system components.

 

You are correct that the PCV Valve should have a positive pressure. Its job is to recycle the pressure from the valve cover area built up into the intake manifold. If you are getting a negative pressure you may be looking at the breather valve, wrong side. Check on the other side of the engine and look for the 1/2" hose that leads into the intake manifold. On my hemi its on the passenger side towards the rear of the car. Sidenote: Parts America doesn't list the PCV valve as a part they have in stock to replace it.

 

So I am in need of a PCV Valve for my 2005 Dodge Ram 1500 5.7L Hemi. I've looked all over the internet and can't seem to find one for an 05 5.7L. I've found sites that have them for every other year and engine size but not what I am looking for. Advanced Auto in my local area does not carry one. I REFUSE to purchase from our overpriced local dealer.

Anyone know where (ie. website, store, etc) I can purchase a PCV Valve for my truck?

Thanks
Chris

 

I also replaced the PVC on my Dodge Dakota.. purchaced the piece from Autozone. from AZ-Filters if you need the part number I will look it up for you.