Possible PCV issue?

Scotty_R8

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So I purchased my 04 RC earlier this year and it was obviously not treated correctly in the past. It seemed a bit sluggish IMO and over the past year I've been trying to do some routine/preventative maintenance. I just spent the last 5 months deployed and recently got back and went to take care of some things. I had ordered the demon coil packs, venom wires, plugs, and other misc things throughout the truck. Now here's my issue.

When I had pulled #9 plug, it was completely soaked in oil. I noticed a good bit of oil from around where the valve cover meets the head so I replaced both valve cover gaskets. I put it all back together and it sounded like the truck was misfiring like no other. I verified the plug wires were fully seated and in the correct location and still no luck. I had been told that the demon coil packs were prone to that issue so I just went and got replacements from O'reilly's.

I swapped them out and everything seemed to be good except the idle was a little rough and I could hear what sounded like a vacuum leak. Sure enough the elbow coming off the driver side valve cover was split. After replacing that, it still had a rough idle but after a few seconds, I could hear a faint squeal that gradually got louder and louder almost like a bearing on a pulley. Shut it off, checked around and couldn't find anything. Cranked it up again and same issue. A buddy of mine just happened to pull the dipstick a few inches out of the tube and the noise stopped and idle went back to normal. We verified that a few times just to make sure it wasn't coincidental.

At this point I'm at a complete loss as to what to look for or what could be the issue. I'm thinking it has excessive crankcase pressure which sounds costly.
 
To add to all of this, there were two other guys helping when everything was pulled apart and then two weeks went by before putting it all back together. with all those hands in the "cookie jar" it's possible something was hooked up incorrectly on the pcv side. does anyone have a diagram of where all the vacuum lines go to?
 
It does sound like it could be excessive crankcase pressure. First inspect that the hoses from both valve covers are routed correctly (not kinked or plugged).

If that checks out, next I would say you need to pull the valve covers and look for a plugged/damaged baffle. One of the valve covers, I believe, has a fixed orifice that "meters" the crankcase vent flow rate during periods of high manifold vaccum (instead of having a PCV valve). If this orifice becomes plugged, then crankcase pressure builds up can cause the symptoms you describe.
 
It does sound like it could be excessive crankcase pressure. First inspect that the hoses from both valve covers are routed correctly (not kinked or plugged).

If that checks out, next I would say you need to pull the valve covers and look for a plugged/damaged baffle. One of the valve covers, I believe, has a fixed orifice that "meters" the crankcase vent flow rate during periods of high manifold vaccum (instead of having a PCV valve). If this orifice becomes plugged, then crankcase pressure builds up can cause the symptoms you describe.

Thanks for the info, i'll give it a look. Also to add, I believe the two lines coming from each valve cover was T'd underneath and had a single line to the catch can. The small orifice on the bottom of the intake manifold was capped. the large opening on the front of the intake manifold left of the TB is ran to the CAI and the small line on the bottom of the TB runs to one of the lines that runs parallel to the drivers side valve cover on the outside.
 
It does sound like it could be excessive crankcase pressure. First inspect that the hoses from both valve covers are routed correctly (not kinked or plugged).

If that checks out, next I would say you need to pull the valve covers and look for a plugged/damaged baffle. One of the valve covers, I believe, has a fixed orifice that "meters" the crankcase vent flow rate during periods of high manifold vaccum (instead of having a PCV valve). If this orifice becomes plugged, then crankcase pressure builds up can cause the symptoms you describe.


Vacuum is hosed from the intake manifold from behind the throttle body underneath to the driver side valve cover. (Some of us install a Closed Catch can in the hose from the intake to the driver side .....)This is the one with the Orifice. You may need to remove the valve cover and confirm the orifice is still there. the passenger side hoses from the valve cover to the intake air filter. Clean air can be directed into the engine during high vacuum conditions.... Hope this helps. :)
 
On the '04 both valve covers are T'd together and run to a port just aft of the throttle body. On mine I just plugged the port and ran it to a catch can. Some folks run it to the catch can and then back to the port instead of plugging it.

Is the whistle due to vacuum or pressure ? You might be able to play a bit with the oil fill cap and "feel" it. I would expect it to be pressure in which case your line / catch can is plugged. There are NO orifices or small ports in the valve cover lines or fittings on an '04.
 
Vacuum is hosed from the intake manifold from behind the throttle body underneath to the driver side valve cover. (Some of us install a Closed Catch can in the hose from the intake to the driver side .....)This is the one with the Orifice. You may need to remove the valve cover and confirm the orifice is still there. the passenger side hoses from the valve cover to the intake air filter. Clean air can be directed into the engine during high vacuum conditions.... Hope this helps. :)

Thanks for that. So where does the larger one on the front left of the TB connect to?
 
On the '04 both valve covers are T'd together and run to a port just aft of the throttle body. On mine I just plugged the port and ran it to a catch can. Some folks run it to the catch can and then back to the port instead of plugging it.

Is the whistle due to vacuum or pressure ? You might be able to play a bit with the oil fill cap and "feel" it. I would expect it to be pressure in which case your line / catch can is plugged. There are NO orifices or small ports in the valve cover lines or fittings on an '04.

I may have worded that incorrectly. The initial sound was from the elbow's and had a vacuum sound. after fixing that, the second sound had an almost metal on metal sound. the orifices I was referring to were the elbow's on the very back of each valve cover.
 
You need to separate the hoses from the valve covers. with them both Tee'd together you will be pulling a lot of oil into the intake and pulling a large volume Vacuum in the crankcase. It will show as a Vacuum leak. and create the whistling you are hearing by pull air in wherever it can ..... Separate them as I described earlier. Are the baffles missing from under the valve covers?
 
Thanks for that. So where does the larger one on the front left of the TB connect to?
There are 2 3/8" barbs under the throttle body. one goes to the valve cover. The other goes to the brake booster..... there are taps that go to the vacuum accumulator behind the cowl and the cruise control servo and some other gizmo tied into the evap system..... I am going by memory....... :)
 
Here are some images that will assist in getting the crankcase evacuation set up properly...

OEM fresh air into crankcase (keep separate from rest of system)
McNally C.C. Overview with OEM Clean Side Feed II.jpg
Drivers side valve cover with "metered" nipple for intake vacuum to draw from (or feed into external catch can)

OEM Metered Nipple on drivers side.jpg

Main vacuum draw from under intake. OEM has this attached to drivers side nipple. (or, attach this to vacuum draw on external catch can).

CCV Vacuum nipple under intake (Capped).jpg

Good luck. Cheers!
 
Here are some images that will assist in getting the crankcase evacuation set up properly...

OEM fresh air into crankcase (keep separate from rest of system)
View attachment 63175
Drivers side valve cover with "metered" nipple for intake vacuum to draw from (or feed into external catch can)

View attachment 63176

Main vacuum draw from under intake. OEM has this attached to drivers side nipple. (or, attach this to vacuum draw on external catch can).

View attachment 63177

Good luck. Cheers!
Thanks for that info. I'm not sure if it's different year by year but mine doesn't have the other nipple on the front of the passenger valve cover like yours does.
 
Thanks everyone for the help. I ended up starting at the very beginning and re-ran everything and it appears to be working now. only issue i'm having is a P0210 code but I think it has to do with too much strain on the #10 injector.
 
On the '04 both valve covers are T'd together and run to a port just aft of the throttle body. On mine I just plugged the port and ran it to a catch can. Some folks run it to the catch can and then back to the port instead of plugging it.

Is the whistle due to vacuum or pressure ? You might be able to play a bit with the oil fill cap and "feel" it. I would expect it to be pressure in which case your line / catch can is plugged. There are NO orifices or small ports in the valve cover lines or fittings on an '04.
If your 04 has both hose tee'd together, you have a large vacuum leak through the engine...... :)
 
So I purchased my 04 RC earlier this year and it was obviously not treated correctly in the past. It seemed a bit sluggish IMO and over the past year I've been trying to do some routine/preventative maintenance. I just spent the last 5 months deployed and recently got back and went to take care of some things. I had ordered the demon coil packs, venom wires, plugs, and other misc things throughout the truck. Now here's my issue.

When I had pulled #9 plug, it was completely soaked in oil. I noticed a good bit of oil from around where the valve cover meets the head so I replaced both valve cover gaskets. I put it all back together and it sounded like the truck was misfiring like no other. I verified the plug wires were fully seated and in the correct location and still no luck. I had been told that the demon coil packs were prone to that issue so I just went and got replacements from O'reilly's.

I swapped them out and everything seemed to be good except the idle was a little rough and I could hear what sounded like a vacuum leak. Sure enough the elbow coming off the driver side valve cover was split. After replacing that, it still had a rough idle but after a few seconds, I could hear a faint squeal that gradually got louder and louder almost like a bearing on a pulley. Shut it off, checked around and couldn't find anything. Cranked it up again and same issue. A buddy of mine just happened to pull the dipstick a few inches out of the tube and the noise stopped and idle went back to normal. We verified that a few times just to make sure it wasn't coincidental.

At this point I'm at a complete loss as to what to look for or what could be the issue. I'm thinking it has excessive crankcase pressure which sounds costly.
Remove valve covers take the tin plate out of the inside and inspect the wadding Its probably packed with goo. The wadding is not serviceable and is made of nylon and breaks apart if you try to clean it I replace mine with steel wool and works well
 
Remove valve covers take the tin plate out of the inside and inspect the wadding Its probably packed with goo. The wadding is not serviceable and is made of nylon and breaks apart if you try to clean it I replace mine with steel wool and works well
Thanks!. I pulled both sides once again and cleaned everything, ran all new vacuum lines and it seems to be running quite well aside from the pesky down stream o2 faults on a cat-less vehicle.
 
Thanks!. I pulled both sides once again and cleaned everything, ran all new vacuum lines and it seems to be running quite well aside from the pesky down stream o2 faults on a cat-less vehicle.

Those can be fixed with either (1) a tune or (2) a pair of simms.
 

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