Mechanics

BLUE SMOKE ON COLD STARTUP

1996 Toyota Corolla

Engine Mechanical problem
1996 Toyota Corolla 4 cyl Two Wheel Drive Manual 175000 miles

My engine was totally rebuilt last month and I have taken it back three times because it blows blue smoke for a second or two on startup. The last time the replaced the valve guides and seals. Again. No change. They cant find the problem. The hitch is that it ONLY does it if it is pointed uphill when it is parked. It doesnt do it on flat ground or when pointed downhill. We are all stumped. My next plan is to pull the PCV out just before I shut it off and see if crud is running down into the injection horn when it is on that angle, which would indicate that the valve stuck open. If thats not it, I am totally stumped. Any other stuff I could check?
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Dbm
September 12, 2009.



Blue smoke on start up is generally valve stem seals, ask them if they put the silicone seals on the exhaust and Viton on the intake.

But oil is getting either past rings or into intake.

Check the PCV and I would also run a compression test on each cylinder, If OK, then have a leakdown test performed.

Mmprince4000
Sep 13, 2009.
Thanks for the thought but it is more elusive than that!
Seals and guides have been replaced twice now because the rebuilder thought that was the problem. Originally the engine was tiotally rebuilt because the compression was bad on two cylinders. Leakdown was performed by my shop after engine was reinstalled and it checked out fine. The odd thing is that on flat ground and pointed downhill it doesnt smoke on startup, Rings valve seals and guides would leak regardless of position, so it is something else. That is why I thought that the PCV may be stuck open and oil may be running into the the intake manifold when the car is pointed uphill.

Tiny
Dbm
Sep 13, 2009.
May be the PCV valve, at least it is the cheapest solution : ).

Remove the PCV hose and check for oil in hose.

Mmprince4000
Sep 13, 2009.