Replace the IP fuel return line with diesel rated clear tubing and watch that line while a friend starts the truck,if it contains a lot of bubbles then air is getting the fuel system while parked.
Often that happens from the fuel heater or water in fuel sensor O-rings in the filter housing.
If the bubbles persist after the engine clears up and runs decent,an air leak between the fuel level in the tank and the LP is the likely cause.
Prove the LP is operating properly as well,with the engine idling,open the WIF drain valve and observe results.
If the engine stalls quickly the LP is not working and needs diagnosed.
If a decent stream of fuel flows out the line and the engine continues to run you have a strong LP.
On 94's,the OS electronic noise filter could be part of the problem as well,remove it completely and plug the OS harness directly into the OS-then get enough ferrite core to cover each OS harness wire(3 pieces IIRC).
After 19 years some things begin to get past their useful age and substitutes need to be made.
Last edited by racer55; 01-30-2013 at 10:51 AM.