Hi Fellow Jeepers, new to posting but have found many answers from the collective genius here. I have a 2001 TJ Sport, 4.0L, Automatic (I know, but she don't stall in low range jaunts). I am experiencing an intermittent issue that I hope someone out there will have some ideas on what it may be: When accelerating under load between 2,000-2,500 rpm I sometimes get a loud fluttering noise. I have read some other posts on fluttering noises, but they always seem to veer off course and talk about blower switches and such. My issue is just fluttering/v-r-r-r-r-ing on acceleration and sometimes on kick-down while passing. Also, after such an event she seems to idle rough until the next run cycle. Some type of intake or exhaust thing? New coil pack, new O2 sensors (NTK), dreaded K&N CAI. The first time this happened was just after transmission rebuild, but I think that was coincidental. Not sure if charcoal canister (?) or vacuum (?) may be suspect. Idles perfect and runs great, other than the occasional gremlin growl... Any ideas?