1998 Mitsubishi Eclipse Blue Smoke.

1998 MITSUBISHI ECLIPSE
116,979 MILES • 4 CYL • 2WD • AUTOMATIC
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SFLEMING
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  • 3 POSTS
my car is blowing blue smoke from the exhaust occasionally when it's decelerating. i think its my valve stem seals but idk? any message about how to change these? also oil is coming out of my valve cover seal.
Apr 13, 2010 at 9:49 AM
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KHLOW2008
  • ✓ASE Certified Mechanic
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Hi sfleming,

Yes, most probably the valve seals are bad.

The normal way to replace the seals are to rremove the cylinder head and perform valve lapping and replacement of the seals.

Alternatively you can remove the rocker arms and with plugs removed, apply regulated compressed air into the cylinder to enable the valve springs to be removed without the valves dropping into the cylinders. Valve seals can be removed and replaced.

The valve cover seals can be replaced at the same time.
Apr 21, 2010 at 10:08 AM
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SFLEMING
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alright well every body is telling me it's not that, its my oil rings? how do i know?
Apr 29, 2010 at 8:09 AM
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KHLOW2008
  • ✓ASE Certified Mechanic
  • 41,814 POSTS
  • ASE Certified Mechanic
For a start, engine nowadays seldom have problem with the oil rings. The valve seals would account for at least 70 % of the smoke.

If it is a fault with the oil rings, the blue smoke would be intense mostly at high rpms.

For valve seals, the smoke would be present at cold start and would decrease. Revving the engine would increase the smoke.
Apr 29, 2010 at 8:19 AM
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SFLEMING
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  • 3 POSTS
well thank you.
Apr 29, 2010 at 8:26 AM
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KHLOW2008
  • ✓ASE Certified Mechanic
  • 41,814 POSTS
  • ASE Certified Mechanic
You're welcome.

Have a nice day.
Apr 29, 2010 at 8:59 AM
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