I am a frequent reader of these forums and have found those who post VERY helpful.
I have a 2000 jeep tj sport. You can see it on my profile. The only changes to stock that might contribute this problem are plugs and muffler. The rest is surface stuff.
When I start my jeep cold, it starts up within 2 seconds of turning the key witn not cranking. If I start it up hot.... within 30 minutes of it being run previously, it starts up just as quick.
If I start it up warm... anywhere from an hour to three hours of sitting, It cranks for 10-30 seconds before starting. I have a red top battery so I am not concerned of it cranking to a drained battery, but feel I will eventually destroy my starter.
Any one else experienced this issue? Any ideas? I have been told maybe the plugs, which are about a year old now.... 20k miles max or the fuel pump. Any other thoughts?