93 jimmy cold start trouble

I have trouble starting my 93 jimmy in the morning. The engine turnes over but after some ignition in the cylinders its still turning over but there is no ignition in the cylinder. I replaced the fuel filter, but i still have trouble starting it after its been sitting for few hours. Might be the fuel pressure regulator? if yes is it hard to find/replace.

Get a fuel pressure gauge on it and post back cold cranking fuel pressure.
Also what engine.
How many miles on tune up?

4.3 vtec, it had a full tune up about 8 or 9 months ago.

The 4.3 W code engine needs 55/61 lbs of fuel pressure to start and run right.
If injectors do not get full pressure around 60 lbs on a cold start they will not squirt.
Get a fuel pressure gauge on it.
Post back all pressures readings eng run eng start and eng running on the road.
MT
Also watch for fast leak down.