I guess a majority of new posters have just signed up to ask about a problem they are currently having. It will be a one time thing for them.
So to activate a new account, if I remember correctly, you have to list an e-mail and until you respond to the e-mail, you cannot post. In that e-mail, you could put in the tips for getting a good response.
We want everything, but that could lead to identity issues for some. For example, the climatic conditions where they live could affect a certain problem, so we would like to know where they live, but they may not want to divulge that information. If they think that climate would be a factor, they could say something like “the northeast”.
Anything that pertains to the problem should be shared. Year, make and model for a car problem would be a minimum. Engine size if this is an engine problem. Manual or automatic if a transmission problem. Date of the show if they are responding to something they heard on the air.
In the e-mail, you could include a link that takes them straight to “Ask a Question” as a lot of people miss that box.
If we get too specific on what info we want, then I could see a post that goes something like this
“2000 Chevy Malibu, V6. Live in the south. I just want to say that the info you gave the caller on that show is bogus.”