After sitting for a period of time (and it takes less inactive time as it gets worse), the engine turns over much longer than normal before igniting. The spark plugs were just replaced and it was tuned up and the battery checked - but the problem persists. It seems to get worse (turn over longer before igniting) but has never failed to start. Normally takes ~1 second or less for ignition. In the current condition it is routinely taking 3 - 5 seconds.
Actually just found this reply to someone else asking the same question on another site:
“The problem is indeed the fuel pump, the mechanic told me it was having trouble holding pressure so when I would let my jeep sit for a while it would depressurize(word?) lol… I guess I had a hole or crack in my fuel pump, also the 2-3 seconds it took to start, started getting longer as the days grew on, right before i took it in to get it fixed it took a good 5 seconds to start so EEK D: hope this helps!”
Any chance someone could second that opinion?