If the PCV hose is clogged, it may cause poor fuel economy. This is because the vacuum on the intake side of the cylinder head will not be able to properly signal the correct amount of fuel that needs to be fed into the engine and can result in a lean or rich engine condition.A clogged PCV hose can produce a number of symptoms. For example, you’ll notice one or more of these symptoms:

• Increase in internal engine pressure
• Failure of one or more oil seals or gaskets
• Engine oil leaks
• Moisture and sludge buildup inside the engine

 

"If the PCV hose was clogged". It wasn't clogged up, it was fine. The baffles in the cam cover that would normally serve to reduce the amount oil vapors entering the vacuum pipe were not functioning properly. Thereby allowing oil to enter the intake system.

By disconnecting the vacuum pipe and plugging it I stopped the vacuum from pulling the oil into the intake. By venting the crankcase, via a hose off of the back of the cam cover, I am allowing any pressure in the crankcase to be vented to the atmosphere. With no crankcase pressure there will be no oil leaks or any of the symptoms mentioned in the previous post.

 

 

Good bye.

 

Too funny^^^

Gotta love folks who beg for help, are told what's going on with their truck and how to fix it, but then don't want to do what it takes because the answer isn't convenient or easy.

 

Can you point me to one reply the actually told me what to do correct the problem? If there is one I missed it and if you can point it out I will gladly try it. The one suggestion I did not follow was to change the O2 sensors.

 

Look here::::::::::::>>>>>>>>>>>>>>>>>>>Oil sucking out PCV

 

Thanks for posting that. If that thread was part of this topic I never saw it.

It does help to confirm my problem is with the baffles. However, like the guy in that post, my baffles are open, not plugged or restricted. I did as he did and blew air in through both of the ports on the cam cover. When air went in one it came out the other. It would appear as though there are no baffles in there or for some reason they are not restricting the flow crankcase vapors. The solution is likely the same as the other guy did; replace the cam cover with a good one. Which I will do someday in the future.

In the meantime I will continue to vent the crankcase to the atmosphere. For two weeks now the vehicle is running fine. No smoke. No oil leaks. Doesn't use oil or antifreeze. Runs like it has done for the past 12 years of ownership.

And I do truly appreciate the help offered here.

 

It's now time to replace the cam cover. I reconnected the PCV hose and the very next day the blue smoke returned. The problem must be in the baffles.

​I do have a few questions. One, is the correct part number for the cam cover 12631008?

Second question is about removing the spark plugs. After getting the Hummer back from the shop I wanted to do my own compression test to verify what the shop told me. However, when I tried to remove the plugs, using a standard 8" ratchet, I couldn't get them loose. My fear was that using a breaker bar would just strip the threads out in the head. Do you have any suggestions on how to safely remove the plugs?

Thanks again for your help.

 

ONLY REMOVE FROM A COLD ENGINE!