Low compression one cylinder

87,000 MILES • 6 CYL • FWD • MANUAL
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RICHRO
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3000 Mitsubiti engine has low compression 50 lbs in #6. Car idles smooth slight puff sound in exhaust. When accellerating feels like a miss under 2K rpm, above that runs smooth.
Mar 6, 2011 at 8:31 AM
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CARADIODOC
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Perform a cylinder leakage test. That involves pumping in compressed air at 30 psi with that piston at top dead center on the compression stroke. Listen at four places to identify the cause of the leakage / low compression. Tail pipe: burned exhaust valve. Throttle body: burned intake valve. Bubbles in radiator: leaking head gasket. Oil cap or dipstick tube: worn piston rings.
Mar 6, 2011 at 8:35 AM
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