New here. I have a 2017 Rtl E with 28000 mls about a month ago the emission alert came on, took it to dealer and they replaced the head knock sensor said if it wasn't under warranty it would have cost $8 to 900 to replace. Last week the warning came back on, they said they had to replace the other head knock sensor apparently there are 2. Has anyone ever heard of this before or is it common?

 

welcome to the forum. I have not seen this happen to date or heard of it on a ridgeline, civic or accord yes not the truck. not aware they had 2 sensors. also fixya shows labor 235-396.00 with parts at 51-63.00. dealerships are expensive due to the great overhead they have.