2 days ago my radiator cap came off somehow... so i filled the reserve tank and radiator back up, and drove it. i let it sit for the night then drove it the next day hoping to have no problems, but my car started smoking, so i shut it off and checked it out and nothing seemd to be leaking. today i popped my hood and noticed that only 1 of my fans was working, and my engine was extremly hot and had a slight burning smell. are both fans supposed to be working at the same time? i dont wana be driving my car then have my radiator go out and be screwed.