longtravel1

I have a 89 XJ that when started will die in 5-10 seconds. i replaced the map sensor to no avail. The vaccuum line from the MAP runs into the throttle body. going to replace the line and grommet next. It will start rough and run with this line unplugged but not correct, Anyone with Ideas????

BuckB91XJ

Longtravel1......are you sure this is a problem with the MAP sensor? You might be barking up the wrong tree. Have you checked your fuel pressure at the fuel rail test port?

longtravel1

No I have not. The JEEP will run with this vaccuum line unplugged. Makes me think it is not fuel pressure related. I do not have a gauge. Can you use a good tire pressure gauge or do I need a Fuel gauge? I think I am supposed to have over 31PSI?

BuckB91XJ

The correct fuel pressure is 31 PSI. You are right, though. If the fuel pressure was bad, it wouldn't run no matter what. So, the MAP sensor and related plumbing probably is the problem.

gabe

i have a 92 w/same exact problem,did u ever figure it out?

longtravel1

No Gabe, I am still battling the problem. I have replaced the MAP sensor, some vaccuum lines, distributor cap and rotor, plugs and STILL have not gotten any progress... If you have any info for me let me know. I hope that someone can help us!!!

mudallday

i had the same problem and i bet its the same thing. open the hood and look on the drivers side next to the air box... there is a ballast resistor that ha two wires going to it. the wires are both orange and black... unplug voth of the wires and bridge the two by putting i wire that connects them both and start it. i willing to bet thats your problem. ll the part does is after a few second it does something to make the fuel punp run quieter. if it runs with the wires bridged try cleaning the resistor or just perminitly connect the wires. i hope this solves your problem.