Q: My 02 Chevy Trailblazer Has a rough idle and sometimes the RPMs go up withiot the car increasing speed

The first thing to check for in any idle or drivability problem is air leaks. Any air that gets into the engine without being measured will lean out the system and cause problems. Look at all the rubber hoses and boots under the hood to be sure they are well connected and in good condition. I’m more concerned about the engine speed going up without the car accelerating. It could be that some component in the automatic transmission is slipping. You should have that checked out. You can do that at your convenience by contacting YourMechanic. The can send a technician to your home or office to check out your Trailblazer and let you know what it will take to solve your problem.