Having problems with your 1998 GMC Yukon ?
Oil running out my tail pipe
\015 I own a 98 Chev trk with a 350 motor.I have motor oil running out the tail pipe,could this be a valve issue?\015
Excess engine oil can only enter combustion chamber from four areas, (1) the intake manifold [pcv system failure], (2) Valve stem seals worn out [pluged oil return holes in heads causing oil to get sucked past worn seals] (3) Worn/varnished up/broken piston rings,(4) Highly unlikely but a hole in piston. Since you only show excess oil on left rear, suspect #2 or #3 although usually more than one set of rings will wear out or (gumm up).Check compression with all plugs out, ignition & fuel disabled, i believe 120 to 150 psi is good, if ok , check #2. If this has the older efi intake, its rare, but also could have a failed intake gasket for that cylinder and be sucking oil from underneath.Hope this helps!
Repair Help & Product Troubleshooting for 1998 GMC Yukon
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