blue smoke out of tailpipe with good compression

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eliterit
Posts: 404
Joined: Sun Dec 21, 2003 9:22 pm
Car: pignose
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i know blue smoke means that im burning oil, but what could cause this if my compression numbers are well within spec. I only get smoke coming out whenever i come to a stop for a while and then take off.

this is on a ka24de


navysnail
Posts: 3335
Joined: Wed Feb 11, 2004 1:33 pm
Car: 1990 Nissan 240SX fastback

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compresion rings are what will make you loose compresion. each piston has 2.oil rings are like windshield wiper blades for your pistons. they wipe away the excess oil from the piston walls. there is one for each piston. if the oil rings are bad, then it is possible to burn oil with good compresion.

the other possible source is the valve guides. it may burn more oil at idle because of the high intake vaccum, and it is usually the intake guides that go bad. the fact that you burn oil when you go from idle to acceleration leads me to belive it is probobly your valve guides.


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