Probably the upstream o2 sensor (could be downstream). Had the same problem, took me a while to figure it out. Easy fix. I replaced both 02 sensors for about $100.
The PCM is also the regulator.
A 2003 Jeep does not have a distributor.
The engiine computer is also the regulator.
No
The engine computer is the voltage regulator.
The engine computer is the voltage regulator in a 1997 Jeep Grand Cherokee.
If this vehicle does not have an electric fuel pump, then the fuel pump diaphragm has a hole in it. Replace the fuel pump. If it is fuel injected, which I think it is, then you have one or more fuel injectors that are bleeding off after shutdown. Have the fuel pressure regulator and the injectors checked.
The 4.7 does not have a distributor.
The only differences are between a regular Cherokee and a Grand Cherokee.
Yes, the engine computer is the voltage regulator.
The engine computer is the regulator.
The engine computer is also the voltage regulator.