Follow my thread "Check Engine (p0171, P0330)" to see how it turns out. As I started to research my particular problem, I learned that the Toyota-Lexus V6 engine has had sludge problems. The sludge problem is an engine design problem and has nothing to do with how well you maintain the engine; the heart (and most important part) of any automobile is the engine.
That leaves the transmission, the second most important part of an automobile. There are some reports (mine included) that suggest the RX300 transmissions may be unreliable.
To see if it would be worth purchasing a used RX 300, calculate the percent cost of replacing and engine or transmission to the used car price of the RX300.
Traditionally, how well you maintain or take care of a Toyota-Lexus automobile has determined the length of trouble free service life of the vehicle. However, if the automobile has a poorly designed part or system your maintenance care may not make a difference in the failure of the part.
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