Lexus Repair: KNOCK SENSOR, lexus cars, lexus 300

Question
CHECK ENGINE LIGHT WENT ON.
ZAK,
AUTO ZONE STORE PLUG IN DIAGNOSIS: TROUBLE CODE PO33O INDICATED MALFUNCTION IN ELECT CKT FOR KNOCK SENSOR.
ASKED MY MECHANIC TO CONFIRM ,HE SAID BOTH SENSORS WERE BAD AND WOULD BE APPROX $900+ TO FIX .THIS VEHICLE 96 LEXUS 300 HAS 130,000 MILES. SEEMS TO SHUDDER WHEN ACCELERATING NOW IN THE 40MPH AREA. COULD IT BE SOMETHING ELSE OR IS THE KNOCK SENSOR THE LIKELY SUSPECT. THE VEHICLE WAS WELL MANTAINED.
 ANY HELP APPRECIATED(PS CAN I PUT IT OFF FOR ANY LENGTH OF TIME)
                      HARRY  

Answer
Hello, I would say that I don't think a knock sensor would cause this. They may be bad, but you may have another problem. Remember that you are at a Auto Zone which know nothing to very little about a Lexus. Cars are not cars. I would look for either a Lexus dealer, Toyota dealer or a trained independent Lexus shop.