I have a 1990 LS400 with 125,000 miles. I recently had the engine steam cleaned. Shortly after this, I notice that the Trac light would sometimes come on. Usually only on really hot days. Although the light would be on, I didn't notice any performance issues...until today I've always loved an opportunity to utilize the power of this great V8, so as I was going to pass someone on the freeway, I stomped on the gas pedal, and nothing happened . The car would not downshift. It started picking up speed, but very slowly because it would not downshift on its own. I manually downshifted, and it took off like normal. The Trac light was on. Later in the drive I noticed that the Trac light had finally turned off, so I stomped on the gas, and low and behold, it downshifted like it should and it took off. I called the dealership, who with all of their wisdom, told me that the Trac system must be malfuctioning (duh) and that I would have to pay them $95 for a diagnostic. (Does anyone know of a good Lexus mechanic in Seattle, Washington). I'm at a loss as this is an intermitten problem. I'm hoping that this is not a progressive problem. Any ideas?