I had that as well, and apparently the previous owner did as well. They had some mechanic change the knock sensors with something that wasn't denso, the light must have came back, so the mechanic pulled the CEL bulb... problem fixed HA!
Anyways, while there is a limp mode, you may never experience it. I didn't, but I went ahead and got denso sensors off of amazon... 2 for $60 which was insane and I was worried they were a knock off, but over a year later I am having no issues.
As another poster said, do the harness while you are in there since you won't actually know if it is the sensor or harness giving the code.
There is a good write up by Rock Rat I believe.