21 replies to this topic

[whoa]

rsmigel, on 23 March 2010 - 12:40 PM, said:

Since your compression is OK, your valve seals can't be that bad. Maybe a little smoke at start-up but I could live with that. I'd check the two vacuum lines going to the turbo and the line going to the bottom of the intake pipe. Also check the two vacuum lines going to the front/driver's side of the intake manifold. And check the connection of the pressurized turbo line going to the top of the intercooler. When that big pipe is loose, the car drives exactly like you mentioned (I've experienced it!)

Valve stem seals don't affect compression, because compression is what is produced in the cylinder when the valves are closed. They will cause oil consumption, smelly exhaust, high hydrocarbons in smog tests, and noticeable blue smoke in certain circumstances, and can apparently lead to shortened valve and catalytic converter life-span. What's more, I may be wrong, but I strongly suspect that they are responsible for a lot of the symptoms that people on these forums tend to attribute to clogged PCV systems: smoke out of the dipstick and oil filler cap, lack of vacuum at the filler cap, oil leaks. I had those symptoms, replaced the PCV system (which didn't look too bad apart from a clogged PTC nipple), and didn't notice a change: still some smoke out of the dipstick and the filler cap (which was never very dramatic to begin with), definitely no vacuum, oil still seeping out of the filler cap... Then I replaced the valve stem seals, and no more of that at all.

Mark

[rsmigel]

Yes, I was thinking valve SEATS vs. valve seals. My bad.

But if you're not getting a big plume of blue smoke at start-up, then I suspect it is not the valve seals.

Since you had "LOTS" of oil in the intercooler hoses, I would remove the fresh air hose going to the turbo and the high pressure hose going from the turbo and clean them thoroughly. Then reconnect the hoses and verify that you're still getting negative pressure at the dipstick (PCV is functioning).

Drive the car some and if you later find that you have oil in the inlet hose, then there is a problem with your PCV system. If you have oil in the high pressure line AND the inlet hose is clean, then you have a problem with the turbo.