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Ok, the topic pretty much states it all. When I got the car the previous owner told me it smokes sometimes when started and it needs a new head gasket, which was obvious. I did some research and consulted with some mechanics and came to the conclusion that the valve seals were bad. I pulled the head, replaced the valve seals and head gasket and started the car. All was good. That was before I was deployed for 14 months. Upon returning and starting the car it now smokes much more when started but goes away when warmed up. I inspected the spark plugs and 1 and 3 seem a little oil fouled so I removed the exhaust manifold to find the 1 and 3 ports covered with fresh oil. It seems the same problem is back. I already intend to replace the seals again but I was wondering what is thought of the piston rings or anything else that might contribute to this problem. Do valve seals really wear out that quick? I did drive it for a while wishing it would go away.

they do dry out after sitting for a while. that may be your problem. but there are tests you can do to determine if it is the vale stems.

What test will indicate specifically bad valve seals?

... I've just found oil in my intake. I understand a bad pcv could be the culprit but does this either deny or validate bad valve stem seals? How about the piston rings?

Do a compression then a leak down test to rule out the rings.
Leakdown test is basically a compression test with a little bit of extra oil added to the cylinders by you (cap full works good)
Remember to do this with the engine warm and when you or someone else is cranking make sure you hold the throttle wide open.Dont forget to unplug either the Fuel injection harness or the ecu fuse, dont want to flood the motor . Pull all the plugs to make it easier for the motor to turn over as well.

Now when your driving its not smoking correct?
How about when your coasting in gear ? if it smokes on deceleration its the valve seals.

I understand a compression test but not so much the leak down test. What should I be looking for while/after testing?
It doesn't smoke heavily while driving after all the oil is burnt but I do notice very light smoke while deceleration or in the first second of acceleration and not so much while coasting. I do believe the seals are bad and have acquired a new gasket/seal kit to fix the problem. After everything is done and verified I'll post the results.

The leakdown test will confirm whether or not the rings are good.
By you pouring extra oil into the cylinder it will help seal the rings.

common instances of bad rings.
Compression will increase with the oil added.
A few psi is common but anything over 10-15 psi is a sign. Also if compression varies greatly between cylinders

Example
160 135 160 162. the 160-162 is fine, the 135 i would be worried.

it could be that the oil drain back holes are plugged up, and sitting there

Thanks for the leakdown explanation.
Could you elaborate more on the oil drain back holes? (location,what to look for,how to fix)

what he means is basically a blockage in the oil drain ports in the head, you would have to remove the valve cover to see them