94 YJ with 6cyl auto with 82k on it. The motor is tight as a drum and runs flawlessly. However in the last 2-300 miles it has a slight little tapping noise at idle. the previous owner rarely drove it and I was wondering if the valves ever need adjusting on a YJ or if it is something much more serious. The previous owner said that he had the motor blueprinted (why on earth I don't know). And he may have fed me a line of BS too. Not out of the question. If every used vehicle ran like the owner says it does, mechanics would be out of business!! All in all the Jeep is great, but I am concerned about the noise. I have checked the fluids and all, but not changed them. Just bought the Jeep and have put around 700 miles on it in the past 2 weeks. I am going to change the oil and filters tomorrow and see if that helps. Any info is appreciated.