Background: Back in July I took the blazer on a camping trip to Padre Island(roughly 1200mi round trip). It performed flawlessly until I got close to home. At the first light coming off the highway it died, started right up again pumping the pedal, but was idling horribly after that, had to keep pressure on the pedal to idle smoothly and seemed to be running extremely rich. Anyway, rebuilt it about 2 mos ago, and it was still doing the same thing afterwards. Yesterday I went out to tackle it again, and it looked like the top gasket is extremely wet with fuel, so I tightened all the screws on the top, readjusted everything and it was running pretty decent. Then...after going on a short trip(about 20mi), it started idling rough again. The problem seems to go away after sitting for a while and come back after it has been run for a long period(10-20mi on the highway). Any ideas what I should be looking for? Vacuum looks good, was getting about 15 off one of the front ports at idle.