If you havent thrown this code before on ur current set up, and you havent changed anything other than diagnosing that AC idle issue stuff - i would put my money on a vacuum/boost leak.Welp only after 2 days...I lost boost and threw a p0171 code. I was going to work, had boost and halfway there bam no boost. I was down to almost an empty tank. Stop filled up and no boost. Came home re-checked the hose to the throttle body and it’s on tight. Checked all other hoses and connections...all tight. Cleaned MAF again also. Any thoughts?
read somewhere on here about a loose fuel pressure reg vacuum hose causing this as well.