99 Jeep Cherokee Runs Poorly at Startup



My jeep runs bad when I first start it up, as if it wants to stall. After 30-60 seconds it clears up and away I go. I’ve hooked a pressure gauge to the fuel rail and after it sits a while, the pressure goes all the way to zero. Is this an injector, pump, or regulator problem, or something else entirely? As a side note, this seems to have started right after I overheated due to a radiator that burst. Not sure if that’s related though, but the problem is getting worse every day.



How quickly does the gauge drop to zero?



Some days it can sit all night and the pressure will be still 20 in the morning. Other days (usually when it is hot out) it could drop to zero in 30 minutes.

One other thing I forgot to mention is it seems to help if I cycle the fuel pump a few times before starting it up by switching the ignition on and off.