94 5.2L Magnum running rough

My Barracuda has a 94 magnum swapped in from a Grand Cherokee. Stock injection.
After sitting through the winter, I started it and it's running really rough. It smells like it's running rich. It tries to idle down, almost dies, then idles back up. When I rev it up, it smooths out some, but not as smooth as it should.
Here's what I've checked so far:
No codes from the PCM.
Inspected all ignition stuff: Cap and rotor look good, plug wires checked out, plugs look good except #4 was wet with fuel.
While running, I pulled the idle air motor connector and nothing changed. Pulled #4 injector wiring, no change. Pulled the vacuum line to the fuel pressure regulator and it also didn't change anything.
My next thought was that #4 injector was leaking. Pulled the rails and pressurized the system, no leaks from any injectors. I ran the pump for quite a while and pulsed a few of the injectors with jumpers. They spray fine, nothing weird.

I'm stumped. My next step will be verifying fuel pressure. Other than that, it could be coolant temp sensor?

What else should I check?

Thanks.
-Dave