What a great site. I have a 1991 lexus ls400. It has about 175,000 miles on it. I have only owned it for about a year. Have fixed a few things here and there and the car is in great shape, but. At the beginning of winter I started to notice a little noise comming from the engine. A mix between a rattle and grinding. Only started happening when the weather started to turn cold. NW Indiana. I noticed about a week later the noise got a little louder and then I lost my heat. Took it in to have a guy look at it. He did not want to work on a lexus. Went to another guy who looked under the hood, looked under the hood, heard the now loud rattle grinding sound. Asked if the motor was overheating- no, but I have not been driving it much since the noise got loud. He said that he thought it was the water pump. Said that the impeller bight have broken loose thus the rattle grinding sound. Wants about $695.00 to fix it. Does this sound like it could be the problem. Please help, really short on cash.