I strongly suggest you check out your fuel relay before you open a can of worms. If it's the relay it will be either bent pins where the unit plugs into the cars wiring or it is cracked solder points on the circuit board of the relay. Lift off cover of relay and have a look. Use magnifying glass to examine back of circuit board.
1993 190E 2.3
2000 Toyota 4x4 Tundra