Lexus Repair: List of problems 2, vehicle speed sensor, combination meter

Question
QUESTION: It's A 1998 Lexus ES 300 and she has 147335 miles on her....One more questions....She has all her gauges working besides the speed odometer and trip meter it just stop working didn't notice it til now...What will also cause those two stop working?..Still Stumped

ANSWER: THE FIRST PLACE I WOULD GO TO IS THE VEHICLE SPEED SENSOR ON THE TRANSAXLE. CHECK FOR GOOD CONNECTION. MAKE SURE OUTPUT SIGNAL IS COMING OUT OF SENSOR, IF SO I WOULD NEXT GO TO COMBINATION METER AND CHECK TO SEE IF SPEED SIGNAL IS EVIDENT THERE. THIS MAY TAKE ALITTLE DIAGNOSING RATHER THAN GUESSING.
GOOD LUCK

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QUESTION: Engine is making a knocking noise and its losing power?

Answer
TO MANY VARIABLES NOW IT WAS OVER HEATING. STEAM WAS COMING OUT OF TOP OF ENGINE, SPEEDO DIDNT WORK. NOW ITS OVER KNOCKING AND LOSING POWER. POSSIBLE THAT THE OVER HEAT CONCERN IS RELATED TO YOU'RE LAST INPUT? TAKE IT TO A CERTIFIED TECHNICIAN THAT CAN LOOK AT IT. I CAN JUST GIVE YOU OPINIONS.THEY CAN TELL YOU WHAT THE CAUSE IS AND THE REMEDY.