99 XJ Stumble/Hesistation on Initial Acceleration

[Jonner]

Out of everything I checked and replaced on my jeep, turned out to be old spark plugs. Go figure. At least I have some new parts on there and the wife wasn't complaining about me spending money on the jeep. :conceited

Glad you fixed it! My stumble on acceleration turned out to be a spark plug boot that wasn't fully seated close to the firewall. It was grounding out to the block. I finally noticed it when I heard this clicking sound and checked out the engine bay at night. It looked like little shots of lightning hitting the block. The problem only happened at idle when the engine was warm.

You may have had a similar problem since replacing the spark plugs fixed it, or maybe your spark plugs were just old.