I think you have a decent starting point for a website. (Viewed on Dell Latitude ATG D630 running Ubuntu 14.04 LTS with FireFox 38.)
There are some things that I, personally, would alter. The items in the list are in no particular order.
1. It was very difficult for me to read through the site. The large font is distracting and the pages just seem excessively long. The font size could be one reason it seems so long, I did not do a word count. Found size was probably the most distracting thing throughout the site for me.
2. So many questions. The way I view it is that you are supposed to tell me the solution. If my car has bug guts, tar, etc. tell me you can fix them. The questions in combination with some other statements make you seem very condescending and could very easily insult people. I understand you're trying to be helpful, but you have to keep in mind not everyone cares as much as you or knows any better. Those cheap car washes spend a lot more money on marketing telling people how great their service is, your potential customers may think they've been taking care of their vehicle properly. Here is an example:
Sure, going through the local car-wash on the weekend will make your car or truck look nice and clean but is it really? Look closely at your paint; the fender and quarter panels behind your tires; your front bumper. Better yet, feel the paint. Feel gritty? Are there still tar and bugs attached to your car?
3. Following up with the quote above. Grammar is a major factor in differentiating a professional website from a not-so-professional site. I know the rules of english are rather fluid compared to some languages and vary from country to country but I see some errors.
4. Exclamation points. I see detailing really excites you and that's good. I would definitely reduce the number of exclamations on the site though. To me, again, that shows unprofessional, slightly immature writing.
5. Do you have facts to back up all your claims? I'm not saying that I disagree with them but I promise you there are people that do and you know that someone will ask how, why, or something "clever." Mostly referring to the following quote.
A vehicle that is professionally detailed on a regular basis will maintain a higher resale price and trade-in value. Additionally, you and your passengers are exposed to the environment inside your vehicle every time you use it. A clean interior will reduce allergens and air-borne toxins that may cause adverse health conditions.
6. The minivan picture and the Facebook link on the main page are distracting to me. Dark page, bright borders on those. Keeps drawing my attention away from everything else.
7. Speaking of Facebook. In my opinion, the social media services for a company should attempt to refer you to the main website. You seem to be pushing your social media more than your website. Social media is great if used properly. Here's a link with a few useful tips (you don't have to use Hootsuite to execute them, but it is a good program).
8. It's kind of boring. No need to get extravagant but a little bit of spice doesn't hurt.
Anyway, enough of me sounding cruel. I hope this helps and hopefully you'll grow into a solid business with a solid website. Please note, not trying to bash, just trying to be honest.