several issues

[Ghost Rider II]

I have a 97 ranger 4.0 and have been having problems for quite some time. here is what is happening:

1.) lately it has a gas smell that comes through the vent system when a/c or just fan is on. Also if you have the window open it smells gas when riding and when you stop, but not all the time.
2.) Sometimes it has a slight rough idle at start but smooths out after a minute or 2.
3.) Sometimes it seems like it is pulling a heavy load behind it because it appears to have a hard time maintaining highway speed.
4.) When driving, it has a slight miss or surge in it. Again not constant.

Most of the issues are intermittent. Some times it runs great, other times it feels like it is pulling a heavy load with nothing behind it. gas smell also comes and goes. Can't seem to figure it out. Not throwing any codes either. Bought a Chilton's but useless for troubleshooting problems or telling you how to test for proper operation of sensors, ( IAC, TPS, EGR, DPFE, etc... ).

here is what has been changed:
O2 ( bank 1 upper ), EGR, DPFE, IAC, TPS, MAF, new plugs, wires. PCM and Coil Pack have been swapped with another one, no change. Also checked for vacuum leaks and didn't find any.

I have been told EGR, CAT, and other items. already changed a lot of items including EGR and sensor a little over a year ago.

Can anyone help me figure out what is going on?

 

[windsors03cobra]

I would check the fuel pressure regulator, its on the fuel rail and has a vacuum hose attached to it. When they fail they feed gas right into the intake and can cause some of the symptoms you describe.
Pull the line off and look for traces of gas and also start it up with the line off and see if it leaks.