96 f150, 4.9l

Engine often starts in a low and rough idle. Engine shudders and dosen't catch. Have to try from 2-6 times to get it going. Sometimes strong smell of gas.

I have replaced the fuel filter as it was plugged.

I replaced the idle air fan.

The o2 sensor code is showing on the computer. Fuel pressure, spark plugs seem to be okay.

Any ideas on where I should go next with this?