93 gmc runs really bad after sitting. runs great after warms up and driving on freeway. then runs bad again after parking and sitting. replaced coolant sensor,tps, iac, complete distributer and coil, plugs, fuel filter, checked fuel pressure, rebuilt fuel pressure regulator. made all these changes truck still runs bad. so i decided to take a compression check. all compression from 1 - 7are 145 to 150. got to number 8 pulled out plug and found it was saturated with fuel. had someone turn motor over and saw fuel pumping out of cylinder. changed sp plugs and put new wires. nothing helped. any suggestions what to do next?

 

Fuel injector stuck open.

Would let fuel drip into the cylinder anytime you let it sit, aswell as not firing off fuel at the right time, leading to a misfire (why it runs rough).