I warm up engine aprox 5 minutes ,(at idle)and then mouve it out of garage and run it at fast idle aprox 1 minute , then drive around back to start working and i notice even after running for aprox 15minutes the temp gauge stays cold,I was wondering if anybody else had the same problem (gauge reads low) i'm supecting thermostat, I will check it later with my non contact thermo gun, oh the temp outside is aprox 20 f or -08 celcius