I run into "experts" like that just putting in gas. Most want to tell me about their friend's uncle's brother's original '69 Z28 with a big block.
I deal with those type of people at work. Then I meet them away from work. They're every where! My neighbor has told me I have a rod knocking in my pickup twice now because it's so noisy. The third time he said I probably need to change the spark plugs. I pointed to the word "Powerstroke" on the fender and he didn't know what that meant.
I looked 2 days in GA for a 69 z28 that had AC, he could have been wrong about the AC, I had to go look. No surprise the directions to the car were wrong.
Ya gotta learn to just go "yup, uh-huh, oh I didn't know that", because trying to learn some of these idiots is just a waste of your time. I do have a lot of people ask me what year my car is (1969 seems to be what is guessed the most WTF?), I just try to give them a little knowledge on the different generations.
Lol that's as good as the time someone told me my vette had a 305. I've heard somethings about my Camaro, but they where at least plausible things that people could get confused with. Think the guy was trying to yank yer chain