1998 Lexus GS 400 poor compression in a low mileage vehicle

1998 LEXUS GS 400
125,440 MILES • V8 • 2WD • AUTOMATIC
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PNESS1
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car has 65-85 psi of compression. This is accompanied by excess oil on spark plugs and in tube that links air cleaner to throttle body. Could this be due to a valve adjustment? Or is the motor worn out? The car doesn't have smoky exhaust. Possibly timig belt/chain malf?
Nov 1, 2009 at 6:05 PM
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RASMATAZ
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If both dry and wet test reads this compression pressures-sounds more like valves-do a cylinder leakage test this will tell where its leaking at-
Nov 1, 2009 at 6:36 PM
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RASMATAZ
  • ✓ASE Certified Mechanic
  • 75,992 POSTS
  • ASE Certified Mechanic
Hi pness1 and TY for the donation

If both dry and wet test reads this compression pressures-sounds more like valves-do a cylinder leakage test this will tell where its leaking at-
Nov 1, 2009 at 6:38 PM
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