I suppose there is a chance the intake is leaking, but three things have kept me from considering it as a possibility. One, you're not losing oil, or at least you haven't mentioned it. Two, you're not experiencing spark knock (pinging). Three, the TSB only applies through 1999 models and yours is a 2003.

You might want to stop at the dealerfor an OEMMopar filterand avoid the cheaper aftermarket ones like Fram or STP.

 

My pcv valve has been buzzing since I got my engine rebuilt, 30k miles ago. I've tried 3 different brands, they all buzz. I was stressed about it but Iburn no oil, and have passed my recent emissions tests with flying colors.

An observation.
I have installed a mechanical oil pressure gauge. I 'T'eed the line so the oem gauge still works. The oem gauge rarely corresponds with the rise and fall of the mechanical gauge.

I have driven for 8 hours straight at 65 mph at a constant 56 psi oil pressure with 10w-30. Stopping at a rest area this will drop down to 19 or 20 at idle. After aquick restroom break, I start the van and the PSI at idle goes back up to over 40. Back on the highway it takes a few miles for it to drop back to 56psi from 64psi at 65 mph. Apparently the oil cools down pretty quickly after shutting down.

I was able to remove my oil pump driveshaft easily by using one of those antenna extendomagnet
things from a 99 cent store, and pulling it out the distributor hole and re installing it the same way, but I have no sludge.

I hope you get it sorted

 

Well I just test drove it after installing another new filter. It ran great for the first 5 miles, the engine completly quite and about 50 psi oil pressure,then I noticed the pcv valve starting to rattle my manual pressure gaugestarted to fluctuate needle on gauge moving so fast it was hard to see,between 20 to 30 psi. as I drove the pressure gradually droped down to 10 psi and remained there while moving and pvc valve stayed noisy except when idling. The pressure did come slightly at a idle about 20 psi. I had to floor it to get up my driveway and when I got home the pressure was at 0. as usuallafter shutting it off for a minute or two the pressure came back up but only to 30 psi. So I changed the filter again while it was hot.started it andthe pressure was fluctuating between 0 and 60 psi needle on gauge moving so fast it was hard to see and the pcv valve wasvibrating loudly. Then I let it sit for about 10 min, started it and the pressure was normal about 40 psi and steady. I dont have a clue but the pcv valve rattles every time I start losing oilpressure or the gauge fluctuates rapidly. And at a idle the pcv valve is quite and very noisy when accelerating. I feel like im growing old while working on this van. Thanks again, Allero and everybody on this forum, Dan

 

Sigh! [&o]
Time to inspect the valve train.

 

Thanks again alloro, After reading back through all of your replys going back to the first one wich was right about the pump shaft you also said "Quote" There is a chunk of sludge or other debris in your oil passage leading to the top of the motor. I say the top because you said the bottom stays quiet. At low RPMs the debris just sits there and allows oil to pass. However, when you rapidly accelerate the oil flow picks up dramatically and pulls the debris along until it hits a narrower part of the oil passage. When this happens oil flow is cut off to the top of the motorand your pressure gauge also drops since it reads the pressure up there. Once you turn the motor off, the oil flow stops and the debris is allowed to settle until the next high RPM situation. This still sounds like the right diagnosis, I let it warm up to temp ,runs perfect for 5 to 7 miles then the problems start. Then I looked in my 98 Chiltons manual under oil pressure trouble shooting it said that apulsating gaugemay be from the pressure relielf opening due to a blockage. And I read on another forum about a 318 having carbon build up blocking the pickup and oil ports. The whole bottom end of my engine was almost black inside, I'll send you a picture. I bought this van from my boss and it only had oil changes about every 20k miles, I probably should gave you more of the history on it.Before I remove the intake I'm going to try to flush it out again. The first time I did the pump wasn't working so it never got a chance to get in the oil gallerys. Can you reccomend a good flush to maybe disolve carbon? Please let me know if you thing this could still be the problem. Also as I mentioned before I installed a T between the the dash gauge and the testing gauge, when the pressure drops down to 10 psi on the tester the dash gauge still reads around 40 or more and climbs with acceleration. the dash gauge also seams to work with the wires off and when I lose total pressure it drops to 0. It seems like I have 2 sending units, is this possible? The engine only starts tapping when the dash gauge goes to 0. The motor sounded quiet with the oil pressure at 10 psi on the tester gauge for at least 10 miles.The dash gauge allways reads between 40 to 60 psi until the tester gauge goes to 0 then the dash instantly drops to 0. Thanks again!, Dan

 

There's only one oil sending unit. Perhaps it's an idiot light sender instead of one for a gauge? The ones for a gauge are variable but the idiot light ones are just an on/off switch that open at 2-3psi. This could explain why the gauge reads okay until the pressure drops to zero.

I'm inclined to think you have a sticking valve. If a valve is sticking (open) the compression is getting pumped back to the intake. This is vacuum fluctuation is what is causing the PCV buzzing. A vacuum reading while driving till thebuzzing startsshould confirm this. Also, with the valve sticking there is a lot of play in the rocker arm, pushrod, and lifter assembly. With nothing to hold the lifter down in it's well, this could be the source of the internal oil leak and pressure loss.

 

I flushed it out again, no improvement. Im going to take your advice Allero and check it with a vacuum gauge. I,ll let you know the vacuum results tommorow. I guess the next step is pulling the valve covers. It might be hard to find witch valve is sticking, since it runs fine at first.Is it common for for a valve to start sticking after driving for awhile? Are there any other tests I can do to check for a sticking valve? Thanks again, Dan

 

Dan,

Have you done a Kerosene engine flush?

Kerosene engine flush ...Step by step...

1. Drain oil except one quart, or you can drain all the oil and add one quart of new oil. (starting with a NEW oil filter is recomended).
2. Add the remainder as kerosene, approx. 3 quarts.
3. Start the engine. DO NOT REV THE ENGINE
4. let it run until warm, not HOT, just warm. About 5-10 mins.
5. Drain the entire contents.
6. Add one quart oil, 3 quarts kerosene.
7. Run the engine again until slightly warmer. DO NOT REV THE ENGINE
8. Drain the entire system.
9. You can pour Kerosene into the NON-running engine as it drains out untill it comes out clear.
10. Pour about one quart of oil and let it run out of the oil pan.
11. Add your favorite oil/oil filter.(replace oil pan plug...:razz
12. Run engine until its at operating tempature. Check to make sure it is running ok.
13. Optional...You can drain the system one last time and add new oil filter and oil...

This does a great job...

I would recommend a light weight oil like 5W30 during this cleaning procedure.

Seafoam engine flush is another option since it has other cleaners that would work on the harder crud in the engine.

 

As the engine heats up the valve stem gets hot itexpands and can start binding. This is more likely to happen with an overly dirty engine like in your case because of the crud that can get in-between the stem and the guide wall.

A compression test when the engine is hot is another way to find a sticking valve because there won't be any compression in that cylinder. The problem witha compression test is that it's not reliable in this case because the engine is only turning at cranking speed and a valve that sticks while the engine is running might not stick during cranking.Plus you'd have to pull the plugs quickly while the engine is still very hot which is a stripped spark plug hole and burnt handrisk.

A vacuum test is the best way to go, since you can see what happens while the engine is cold then hot,at idle, higher RPMs, and while driving with an engine load. A sticking valve will cause the vacuum gauge needle to fluctuate quickly. If the needle fluctuations, itwill likely happen at the same as the PCV buzzing noise.

 

Thanks Alloro, I have the vacuum gauge hooked up and ready to test drive but I can't get out of my driveway, too much snow. The gauge reads 17 and steady while parked and idling. The problems won't start until I get out and put a load on it. Is there any way to determine which valve is sticking? Maybe just leave a couple bolts in the valve covers while test driving for fast removal? After determining which valve is bads should I just pull the problem head and free up the valve or do I need a complete valve job or complete clean up? Sorry for so many questions. Thanks, Dan