The Lexus GS300 is a mid-sized rear-wheel drive luxury automobile. Even though it offers high-end performance, fit and finish, the GS300 is like any other vehicle. Eventually something will break. When that happens, you'll need to know how to troubleshoot it. The most important thing to remember is to start with the simplest problems and solutions first and work your way to more complex problems and solutions. This can potentially save you money (and a lot of time).
Look for any kind of colored smoke coming out of the GS300's tailpipe while the engine is running. Blue smoke indicates that you are burning oil. This means that oil is blowing by the piston rings of the piston and burning in the combustion chamber. While not immediately fatal to your engine, it will burn up oil, reduce the lubricant available for the engine and will eventually decrease compression in the engine. White smoke is steam and it means that you are leaking coolant into the combustion chamber. This can cause critical engine failure due to hydro-lock and needs to be addressed immediately. Gray smoke indicates that your engine is running "rich," meaning too much gasoline and not enough air is getting into the engine. This will significantly decrease fuel economy.
Listen for noise in the transmission or the rear differential while the Lexus is shifting through gears. You may be low on transmission fluid. Check and add transmission fluid to the system if necessary.
Look underneath your Lexus to see if it leaking fluid. Black liquid indicates a leaking oil pan reservoir or a leaky seal on the engine. This is the most common problem and can be serviced by a qualified mechanic. Red liquid indicates a leak in the transmission housing, the most common being the rear main seal. Green liquid means that you are leaking engine coolant from the radiator hoses, the radiator or the reservoir tank.
