My old 91 Wrangler with the 4.0L used to act like that except it did it all the time regardless of wether the engine was cold or hot. On mine it turned out to be a bad VSS (Vehicle Speed Sensor) which is located on the transfer case where the speedo cable comes in.
Jeff Hendron 2003 Jeep Wrangler Rubicon MatrixOne Support Skyjacker 4" lift, JKS Disconnects Agilent Technologies Fabtech Front Bumper, Rock Krusher Rear Bumper Co Springs, Colorado Rock Krusher Rock Rails, Custom Swingout Tire Carrier (719) 531-4319 33x12.50 Goodyear MTR's, Mickey Thompson Classic Lock Wheels jeff snipped-for-privacy@agilent.com Bush Whacker Fender Flares, Warn XD9000i Winch
Yamaha WR250ZF
K. Ulicni wrote: : The idle speed on my 2000 TJ 4L has suddenly gone screwy. When I come : to a complete stop the speed drops and the engine will eventually die. : This only happens when it's a complete stop, if I'm moving even the : least bit i'ts fine. It's also normal when cold, if you let it warm up : while parked it will run great until it's warmed up then the idle : becomes gradually rougher until it dies. Any ides?
: Thanks