One problem related to engine knocking noise has been reported for the 2013 Honda Insight. The most recently reported issues are listed below.
Progressive increase in loss of motor oil for the past 12 months. I have to add 1 quart of 0w-20 valvoline synthetic motor oil every 2 weeks! dark smoke coming out exhaust with acceleration. Knocking sound from the motor observed. I used to have Honda accord and never had this problem.