Check Engine Light - Thermostat
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2006 SL65 ///AMG - GONE BUT NOT FORGOTTEN: 2005 E55; 2002 ML55; 2001 CLK55; 1992 BMW 850i; 1991 M5
Check Engine Light - Thermostat
I posted this on the E55 board as well, but thought maybe someone here would have a different perspective. I have one of Patrick's 160 degree thermostats installed in my 05 E55. I think it went in in September. The car runs great and the temp stays either dead-on at 80 degrees or one bar above/below. I live in Kansas City and we had our first blast of winter this week. I drove to and from work with the outside temp in the 20s and the car was fine - one bar below 80 after warm-up. Today was about 40 degrees out and I had to make a highway run of about 40 miles. I was cruising between 80-85 mph and at that speed, the temp stayed below 80. I parked the beast for about an hour and when I got back out to fire her up, I got a "Check Engine" light. I was going to the dealership anyway to have new tires mounted and my tech said the code came back for "faulty thermostat." He remembered putting in the lower temp thermostat and cleared the code out for me and indicated that he wanted to wait a week or so to see if it came back. After the tires were mounted, I fired her up, no CEL, and drove back to the office. Any others out there with Patrick's thermostat have any CEL issues in colder weather? Could it just have been the extended highway trip with only 2200 rpms on the tach, but 80 mph 30 degree air blasting over the radiator? Is this particular error message likely to clear itself out in warmer weather? I love the cooler stat and don't really want the hassle of swapping it in every March and out every November. Any thoughts and ideas greatly appreciated.
