So I've got a 1999 TJ with the 4.0. It's got about 153,000 miles on it and has had an oil change every 3000 miles and every other preventive maintenance issue that I can think off. In about the past 10000 it started making this noise on occaision. It'll only do it if its been starting cold and it always stops after the engine warms up. The wierd thing is that it is not consistent. I may go a month with not a peep. Then the next month it happens 2 or 3 times. I haven't really been able to pin down any rhyme or reason.
Ever since i noticed it I've been putting in midgrade fuel and ran a few cans of seafoam through the gas tank(not in one sitting, over a few tanks of course).
I also went ahead and replaced the spark plugs, wires, distributor cap and rotor.
Still hearing the noise. Any thoughts on the cause and solution? Anyone else had something similar on their 4.0?
See video for the sound, make sure its turned up, the sound is the important part, nothing visually important in the video.