Why does the Check Engine Light keep coming on and how to close the trunk?

http://www.napaautocare.com/estimator.aspx# -- $182 to replace thermostat

I sincerely wish I had some good answers.... but I don't . Other than to say there is no sensor or anything that will light the CEL and have thermostat as a DTC code. Overheating, lots of things but there is no code exists specifically for thermostat. And find another place to have your oil changed.. I caught Jiffy-Lube 'red handed' using Havoline motor oil conventional and I had asked for and paid for Mobil1 synthetic. (Nothing wrong with Havoline, just not what I wanted) And Jiffy-Lube has been busted before for services never done but customer paid for. AND services actually done but unnecessary. Most people don't know or pay attention, they trust the place to do what they are supposed to do but get ripped off. You should be able to trust them, and the vast majority are honest. But I bet they always try to talk you in to a transmission flush also. Right? Don't allow that. Also, if you use synthetic motor oil you can go a year or 10,000 miles. Conventional oil 6 months or 5000 miles (whatever comes first) Personally I don't push it that far, I use Mobil1 and change at 8000. Never a problem. Now, A good alternator will not necessarily keep battery good. The average life-span of a automotive battery is 4 to 5 years. Some will last longer depending on quality and number of start/stop cycles