Why mileage gets worse in winter

Discussion in 'Gen 3 Prius Fuel Economy' started by cwerdna, Oct 30, 2011.

  1. fuzzy1

    fuzzy1 Senior Member

    Feb 26, 2009
    Western Washington
    2012 Prius
    I haven't fiddled with thermostats at all, so will defer to Mendel and others with more experience at them. I'll only speculate that there may be enough other cold air getting in, out of reach of any grill blocks, to keep keep things well cooled.
    My '86 Accord's temperature needle moved around a lot in its old age, and having a shop replace the thermostat didn't change anything much. I didn't further troubleshoot, other than to sometimes turn on AC for the sole purpose of running both electric fans (engine normally used just one of them) for added cooling, quickly bringing down engine temperature.

    Then my '97 Subaru had a rock solid temperature needle. I thought that was great, until getting a ScanGauge and discovering that the entire temperature range from 145F to 210F was condensed to a single point on that analog gauge. :-(
    Mendel Leisk likes this.