Yes, the codes were checked & they indicate knock sensor problems. I deleted
the codes but they returned. My independent Volvo mechanic says it's notunusual
for these codes to return and advised me to forget it as it's basically a non-
problem other than having the check engine light on all the time(the car runs
great, I have all the required maintenance done). I may want to sell the car
some time & figure that a check engine light would detract from the sale.