I think it's also fairly noteworthy that Google found the answer pretty quickly for me.
I can't see anything that makes it off-topic, so I would have to say that it's an okay question. Is it a simple question, yes, but that doesn't make it off-topic.
While we should definitely encourage questions that will attract experts, I don't think we need to necessarily close all of the questions that aren't expert level but still meet our guidelines.
Besides, it's quite possible someone googling that same question might find their way here, which could increase the number of members/viewers of the site. It's not a question that will attract experts, for sure, but I don't think it's going to scare them away either.
The type of questions we need to watch out for are the unprofessional rants that have no place on here and that will definitely detract from the value of the site.
That question aside, I think almost any question on here can be found in the service manual for the vehicle. Not everyone has access to the manual at the time they have the problem. I personally buy the official (OEM not aftermarket) service manual for any car I own. Keep in mind I worked on cars for a living for 20+ years and some people aren't going to go to that extreme. So to answer your question as asked, I would say those type of questions should be allowed.
As for the question you linked to, It seems really simple to me. I almost replied find a spark plug and trace the wire back to the other end. But again I've been working on cars for a long time so things that are really simple to me might be challenging for someone else.