1990 Cherokee fuel pressure demon!

[bandonbound]

Ok. A successful fix. Sometimes on these forums you don't get what the fix was. Here's mine. Had low fuel pressure. Jeep would buck and run bad. Then run good. Did the filter, regulator, and finally the pump. That was it. Pressure rite at 31 lb, jumps to around 35 when you remove the vacuum just like it should. Only advice, take out your existing pump before. Get the brand. A Bosch or Walbro. The parts place asked whether I wanted a Bosch or Walbro. Should have asked, "what do I have, a Bosch or Walbro. I did get the Bosch replacement. A Carter kit, much bigger than Walbro, universal fit and a big headache. Wouldn't go in the hole properly, wouldn't seat and finally took out and swapped for the original Walbro replacement. Super straight forward. So don't do it on a Friday nite in the parking lot. Make sure the parts source you use has both brands. Good luck and thanks to all who helped. 4.3 LXJ especially.

[JENSSEN]

Before you change the pump bypass your balast resistor on the D/S fender and wire it direct. The balast resistor drops the voltage to the pump from 12V to 8V but when they fail they sometimes will not 100% fail they will drop the voltage lower than the 8V and then you have low pressure and a lean condition (engine will run hot). two second test but may save you replacing a pump.

-J

[bandonbound]

Thank for the ballast info. I did that before fortunately. The fuel pump was the culprit. Now, I am having those exact issues with my factory power door locks. Voltage loss. Did read a couple posts about adding relays etc. so I'm onto that. Have only around 5-6v at the actuator and understand its old wiring, factory splicing etc. Thanks again. David in Ca.