Blues smoke, oil burning

[smartrepair]

Hi everybody

I haven´t solved yet the oil burning problem. My 98 2.5 manual Boxter still smokes, although I changed the oil separator. We measured the compression in all cylinders and 5 of them had around 145-150psi, and cylinder 4 had only 135.

Underneath there are some oil coming out around the cylinderhead at cylinder 4 (between the head and valve cover. Also there was oil at the exhaust collector at cyl. 4). The spark plug was a bit oily as well. The rest of the cylinders look fine.

What can it be? A valve related problem?

Here in the Canary Islands nobody knows (!) about the leak-down test suggested in this forum, so I cannot do it.

The local Porsche dealership is moving into another installations and are not attending clients for the next two months....

When I start the car, a lot of blue smoke comes out. When I go to drive to the highway, the smoke disappears. But after the cars stands still for some hours the smoke comes back...

Thnaks

Kare, Spain

[geza]

You may have to remove the exhaust manifolds from the cylinder heads - then you can look up into the exhaust ports using a torch (high powered lamp/light) to see if the valve stem looks oily.

If you know that oil is not leaking down onto the hot exhaust from somewhere outside the engine (failed gasket or something similar) and the cylinder pressures seem OK - the only other place to look is worn valve guides.

Looking up into the exhaust ports will tell you a lot about how each cylinder is functioning with regard to burning oil. Removing the exhaust manifolds is easier than engine removal etc. when you are starting to diagnose the real problem.

[vvortex3]

I am having the same exact issue, looks like alot of other people are. Hoping someone posts to me what they did about fixing it.

[Donie]

A quick substantial puff of smoke on startup, after the car has been standing, is almost always the result of one or more, bad valve stem seals. and seats, which allows oil to leak past into the cylinder, during the period that the car has been stationary for a goodly period of time. The culprit is your number 4 cylinder.