I was told to replace the ECM, the Engine Control Module, to fix an idling issue. Got it from eBay and replaced and fixed it. But to my surprise, AC is acting. Compressor and blower run, but apparently thermostat is not functioning. It blows hot air even I set the Temp at 66! the "Auto" button...

Hi, I have a 2001 Altima GXE with 252,000 miles on it and still rolling. I have a question about P1126 MIL code. The SES light turned on after I refilled the gas with 91 octane (usually I use 87) and after 1 hour driving constantly on a long highway to Yosemite in a bit chill weather of...