HI I HAVE A 99 RX300 AND IT WAS DRIVING FINE 1 DAY THEN THE NEXT I WENT OUT TO START IT TO WARM IT UP AND CAME BACK INSIDE MY HOUSE AND WAS IN MY HOUSE BOUT A HALF AN HOUR ..........THEN WHEN I WENT OUTSIDE TO LEAVE I GOT OIN MY CAR AND I NOTICED THAT MY GAS LIGHT WAS ON SO I STARTED TO DRIVE IT TO THE NEAREST GAS STATION AND THE ENGINE LIGHT CAME ON AND STARTED FLASHING AND I T WAS SHAKING AS IF IT WANTED TO TURN OFF SO I PUT GAS IN IT AND THEN PROCEDED TO DRIVE ( I USE ONLY PREMIUM GAS) THE SHAKING NEVER STOPPED SINCE! SO I TOOK IT TO SHUCKS AND THEY READ THE CODES TOO RICH/TOO LEAN AND MISFIRE ON CYL # 6 SO I WENT HOME AND MY HUSBAND CHANGED THE SPARK PLUGS... WELL 4 OF THEM AS HE SAYS ITS TOO HARD TO GET TO THE BACK ONES SO HE COULD ONLY DO 1 ON THE BACK ! AND THAT DID STILL NOT HELP THE CAR WAS STILL DOING THE SAME. SO I WENT TO A MUFFLER SHOP AND THEY TOLD ME THAT IT WAS SHOWING CODES FOR RANDOM MISFIRE, TOO LEAN AND MISFIRE CYL# 1, 3 & 6 SO THIS IS WHERE I'M AT DOES ANYONE KNOW WHAT IT COULD BE?? I AM CLUELESS AND I WOULD THINK A FUEL FILTER??????? BUT I WAS TOLD AT THE AUTO PARTS THAT THERE IS NO ACTUAL FILTER ONLY A SCREEN THAT SIT AT THE END OF THE FUEL PUMP WHICH WOULD MEAN THAT ITS IN THE GAS TANK ??????? PLEASE HELP ANYONE!!!!!!!!!!!!!!!!!!!! :(