I learned a great tip for cleaning car upholstery today completely by accident.  For the longest time, I've had a dirt stain on the front passenger seat of my car. I've used every car cleaning supply known to man. I even took my big carpet cleaner outside and tried to steam clean it with the attachment, but it would not come out! 

This stain was driving me nuts because my car is pretty new and I like to keep it clean. Today, I was cleaning my car windows and on a whim, decided to spray a little of the Windex on that stubborn stain.  Once I sprayed it, I blotted and scrbbed at it with a paper towel and the stain completely went away! I was amazed.  

Later, I looked online for tips for cleaning car upholstery, and lo and behold, I came across a tip that saying that Windex is great for cleaning car upholstery!  

Another great tip that I learned was that you can create a mixture for dirty carpets in cars quickly and easily by mixing a gallon of hot water, a cup of ammonia, and some dishwashing liquid.  Use a stiff brush to scrub the cleaning solution into the carpet of your car.  Allow it to sit for about 30 minutes and then blot it up with towels.  I was amazed at how clean my carpets looked after using this solution. It's much cheaper and easier to use than  a lot of commercial products on the market.  

You'll just want to try this one in a small area that no one can see - like the trunk, if that upholstery is the same color of that in your car. Unless the carpet in your car is wool, though, it should work fine!