That certainly depends on the job that you are applying for, but in general it is better to slightly overdess than not. Showing up to a job interview wearing a tie where none is expected can actually go in your favor. It shows that you take the interview and the job serious. Wearing no tie in an interview where other applicants do is almost always a mistake. So why take the risk? Wear a tie.
Now the question might come up what kind of tie to wear. The short answer is something conservative and non offensive. Avoid wearing a tie with writing, political or religious meaning, or any images in general. I have seen poeple come to an interview with a tie picturing the American Bold Eagle on top of stars and stripes as a background. This is clearly a no. Showing your patriotism at a job interview is out of place. Your profesionalism and expertiese has to be the main focus.
So what do we consider a conservative tie? Horizontail striped ties are always a good option. Stay away from bright colors such as a sage green or pink. Wearing such bold colors could irritate the person interviewing you and might actually give him or her a reason to judge you without knowing you. Studies have shown that people leave their first impression after less than 20 seconds, way to short to get to know someone.
Now that we have an idea of the tie, what shirt and what colored suit? As far as shirts go, stay with white or light blue. Both colors go with pretty much anything. White is preferred however. An aditional benefit of white is that should you get nervous and start sweating uncontrolably, wet sweat stains don´t show as easly. I am talking out of experience by the way...
That the shirt has to be long-sleve shouldn't be neccessary to mention. Even if applying to a used car dealership this is a clear NO! For the suit stay with dark gray or dark blue. Pin striped suits are fashionable but don't belong in an interview. We are not trying to make a fashion statement after all.
Alright, this should give you a good overview. I have interviewed hundreds of people in my career and first impressions do matter more than you might think, especially when applying for a sales position. Have good eye contact, be polite, smile and be confident. Good luck!