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Smoking after cleaning PCV hole

2.9K views 9 replies 5 participants last post by  Kevireno  
#1 ·
Howdy all, new member and long time lurker with a head scratcher for you.

2005 Canyon 3.5 I5 290k miles and has never smoked up until this point. The following is the background of what is going on.

When I was changing oil last week I noticed the oil wasn’t draining like it should (too slow and with a gurgle sound every so often), so I popped the oil cap. Heard a shh kind of like when you open a coke bottle and of course the oil then overshot the drain pan.

I started investigating why there would be pressure build up, and found out the PCV orifice and breather hole were full of a dark tan slimy substance (not what I’d call 100% milkshake more oil colored). The PCV orifice (the one with the 3/32 hole) was completed stopped up and I used a drill bit (by hand no tool) and pipe cleaners to open it back up. I cleaned out the “Vortec Box” as I call it which was also full of that same slimy substance.
Finished changing oil, and cranked it up no smoke.

The next day I cranked it to go to work and the biggest plume of smoke I’d ever seen came out of the back. It started off white for the first 10 seconds and then switched to blue. Every time now that it sits (while I’m at work or overnight) it will do the same thing although the cloud is somewhat better than it has been.

My question… does anyone have a thought on what’s going on? Could the system be pulling that gunk still after a week? Is the PCV pulling too much vacuum now that it’s clean and pulling oil in? I find it hard to believe valve seals and/or even a head gasket would coincidentally die right after I cleaned the PCV and breather.


TLDR Cleaned PCV orifice, vortec box, and breather, and now truck smokes without any other history of smoking
 
#2 ·
Welcome to the Nation.

Sounds like you had a vacuum situation in the engine, not pressure. If there had been pressure when you removed the drain plug, there would have been excessive oil flow, not slow.

Check the clean air inlet for the PCV. That is the hose going from the resonator to the camshaft cover. Make sure the hose and the fitting in the camshaft cover are both open.

Try isolating the PCV system. Remove the rubber elbow from the camshaft cover fitting. Plug the elbow with something to prevent a vacuum leak. Leave the fitting on the camshaft cover open. If the engine still smokes you probably have issues other than the PCV. Check to see if you have a discharge from the fitting on the camshaft cover.
 
#3 ·
That’s a mistake on my part about vacuum, been a long week already.

To add a little more I cleaned the hose from the resonator to the camshaft cover when I had the resonator off. It had a little bit of residue in it but nothing to write home about . Ran a camera down the PCV elbow (drivers side going towards intake) and it had a very little bit of residue in there as well.

Didn’t think to isolate the system, will do that this weekend and report back.
Thanks for the quick reply!
 
#5 ·
Could be a stopped up Crankcase Vent Hose that vents the Vortex Box. A few years ago mine was mushy, rotten, and kinked over and was impossible to reinstall. Got a replacement vent hose at Auto Zone, problem solved. When you pull off the Vortex Box, you will be looking at it. When it gets mushy, no way can you reinstall it. And, I doubt if even Viagra would help that. After all, it has a "Lazy S " configuration about it.
 
#6 ·
I've got a similar problem. I took the valve cover off over the weekend to clean the pcv cause like this guys saying if it sat for a long period of time (usually 7 to 5:30) i would get a good puff of smoke. Put everything back together and now it's smoking worse. Actually everytime I crank it and burning alot of oil. I have cleaned the hose and opened the cover of the intake manifold to where I can see both rubber 90s. Any help is greatly appreciated.
 
#7 ·
Welcome to the Nation.

While your issue sounds like it might be from the PCV system, the smoking when starting is also a classic symptom of leaking valve stem seals.

Probably a good idea to figure out if there is a problem with the PCV system. or not. Try isolating the PCV system as advised in Post#2. If the smoke problem goes away you can dig into the PCV system a bit deeper. It the smoking, when started, continues with the PCV disconnected, I suggest look into the valve seals.
 
#8 ·
As a general update:
- Isolated the PCV system and no smoke at start up

- The fresh air inlet hose going in to the resonator was replaced last year

-The resonator, air inlet hose, and PCV 90 were cleaned from the outside

-After I cleaned the fresh air inlet and PCV outlet, I have used a quart of oil over ~ 700 miles

Could there be something blocked in the cover that’s making oil some how collect near the PCV outlet and burn off when I crank it?
My smoking only happens when I crank it and for the first few minutes of driving, then it quits. Thanks again everyone for your help.
 
#9 ·
If all other conditions were the same and all you did was isolate the PCV system, it would seem that the amount of oild being drawn out through the PCV is excessive. Not sure how that could happen and if it did, why isn't the engine smokling all the time? Normal discharge should just be a vapor. Also the PCV system wouldn't be discharging anything into the intake with the engine shut down. It might be a coincidence and with 290,000 miles, you could just have valve seals leaking.

Then again, why did the smolking stop when the PCV system was isolated? Weird.