2009 LEXUS LS460 Engine Problems

VEHICLE AT FAST FOOD DRIVE UP NOTES ENGINE VIBRATION, WARNING LIGHTS FOR ENGINE, VSC WARNING, AND INSTRUCT TO TAKE VEHICLE TO LEXUS DEALER ASAP. CAR HAS VIRTUALLY NO POWER WITH 8-10 MPH MAX. LEXUS SERVICE DEPT NOTES VALVE SPRING IS BROKEN AMONG THE 32 VALVES IN THE ENGINE. WARRANTIES HAD EXPIRED. LEXUS OPTS TO REPLACE ONLY ONE DEFECTIVE SPRING BUT HALF OF THE TOTAL NUMBER (ONE SIDE OF V8) WERE REPLACED BY THE DEALER. THERE IS CONCERN THAT UNBALANCE OF SPRING STRENGTH IN THE ENGINE COULD LEAD TO PROBLEMS AT ANY TIME. THESE VALVE SPRINGS WERE THE SUBJECT OF A LEXUS RECALL IN 2007 AND 2008 MODELS OF THIS VEHICLE. 2009 MODELS SUPPOSEDLY USED A DIFFERENT SPRING OR PERHAPS A DIFFERENT SUPPLIER. SOME PROBLEMS WITH 2009S WERE REPORTED TOO. IN 2010 ANOTHER DIFFERENT SPRING WAS USED IN 460 V8. I AM NOT EVEN SURE THAT A 2008 VERSION OF THE...