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Ted G.
Ted G., ASE Certified Technician
Category: Car
Satisfied Customers: 6089
Experience:  20 years auto repair experience, ASE Master Tech, Mechanical Failure consultant, Expert Witness
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1993 GMC: V6..runs great..a quart of oil every 200 miles or so

Resolved Question:

I purchased a 1993 GMC 1500 PU with a 4.3L V6 about 6 months ago. It runs great however it is going through the oil. I have to add about a quart of oil every 200 miles or so. Don''t see any smoke coming from the exhaust.
Submitted: 8 years ago.
Category: Car
Expert:  Ted G. replied 8 years ago.
That engine has some problems with valve seals leaking oil. Over time the oil usage causes carbon to build in the rings and binds them. If the oil control rings bind you will use LOTS of oil. Because you have a catalyst in the exhaust you may not see blue smoke until it gets really bad. You could try an oil change, a new PCV valve, and possibly a top engine cleaning, but frankly if it's using that much oil it will probably need to be rebuilt or replaced when you get tired of putting oil in or it starts fouling the plugs and running poorly.
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Customer: replied 8 years ago.
Reply to Ted G.'s Post: Ted G. The motor was rebuilt about 10K miles ago per the previous owner. I have replaces the PCV valvue and I recently changed the oil (about 500 miles ago). Will a compression test identify bad valvue seals? Obviously, I would like eliminate any other possibilities before I tear into the motor.
Expert:  Ted G. replied 8 years ago.
No, visual inspection is the only way to check valve seals. If it has been done that recently something is very wrong.