I changed to the 170 F thermostat and am getting check engine light on cool days on the hwy. The engine temp is low do to stat and koyo rad and code is low temp. Has any one else had this problem and is there a solution or do I have to go back to stock stat? With the stock stat on hot days in traffic motor runs hot.

 

Wow its cold up there in Canada already? I have a nismo but its still warm here. I will know in a few months.

 

When I said cool I mean below 68 F out side temp in the evening.