2002 Lexus ES Problems: 3 Known Issues

On the 1997-2002 Lexus ES 1MZ-FE 3.0L V6, the 3.0L 1MZ-FE V6 in the 1997-2002 ES 300 is one of the core engines in Toyota's oil-gelation controversy. A combination of crankcase ventilation design and a 7,500-mile service interval let oil oxidize into a thick sludge that coats the valve covers and plugs the oil pickup screen and small oil passages, starving bearings and rings. Symptoms progress from a persistent low-oil-level and blue smoke to a knocking bottom end. Toyota settled a class action covering roughly 3.5 million 1997-2002 Toyota and Lexus vehicles with the affected engines, agreeing to repair sludge-damaged engines for up to 8 years from purchase with third-party mediation for denied claims. That settlement window has long closed, so today this is a buyer-beware inspection item rather than a covered repair.

On the 1997-2003 Lexus ES 1MZ-FE 3.0L V6, on the 1MZ-FE V6 the two knock sensors sit in the valley between the cylinder heads, and their sub-harness bakes there under the intake manifold. The wire insulation hardens and chafes, shorting the signal wire to ground and setting P0325 (knock sensor 1 circuit) and/or P0330 (knock sensor 2 circuit). The ECU responds by pulling timing, so the car runs down on power and mileage with a permanent check engine light. The recurring forum lesson is that the harness - not the sensors - is usually the failed part: owners who replace only the sensors see the code return within days.

On the 1999-2006 Lexus ES, the U140E four-speed (1999-2001 ES 300) and U151E five-speed (2002-2003 ES 300 and 2004-2006 ES 330) automatics used behind the 1MZ-FE and 3MZ-FE have two distinct documented failure patterns. Higher-mileage 1999-2003 ES 300 units slip - typically after the fluid warms up a couple of minutes - as the clutch packs and valve body wear, ending in a burnt pack and no drive. Separately, the 2002-2006 cars are known for a shift-logic hesitation and momentary surge from a rolling start that Toyota treated as a drivability/customer-satisfaction issue and addressed with control software revisions; the 2004-2006 ES 330 in particular drew heavy complaint volume for slow, inconsistent shifting.