Good advice from El-Dracho.
Two more thoughts:
1) Be aware that to travel in some countries in Europe you'll need a vignette (which is a permit to use the roads) -
Austria, Bulgaria, Czechia, Hungary, Romania, Slovakia, Slovenia, Switzerland (that's all of them I think). You can buy them online in most cases.
2) Your question says "importing" which could mean importing (as such) or could mean bringing the vehicle in temporarily as a visitor. For the latter, as noted in El-Dracho's reply, a TIP can be used instead of a carnet. In case you mean importing, with the intent to register your vehicle in a country in Europe, the process is entirely different. I've done this a couple of times, with a USA-registered vehicle and with a Canadian-registered vehicle, and it was fairly straightforward but there are lots of hoops through which to jump, including things like changing lights meet national standards, ensuring that glass meets national standards, and others. In addition there will be customs duty and/or import taxes, and vehicle inspections beyond the simple process for temporary entry.