DoctorJay

The "Check engine" light has been on on my 2006 Fusion for well over a year. The code indicates the engine is running too cool, but to my knowledge this is actually good for the car so I haven't replaced the thermostat. I use full synthetic oil which does not sludge (and to my knowledge running cool does not cause sludging even with cheap oil). Is there a way to permanently turn off the engine light for this code? I've reset it a couple of times but it comes on again in 3 or 4 weeks.