I got a 91 cherokee the fuel pump wont come on the relays are good the pump will come on when you ground one of the prongs in the test port on the ecu under the hood everything else looks fine like fuses and relays please help

 

Does the ignition switch feed power to fuel pump or tell it to come on

 

http://jeep.zerok.ru/index.php?page=196. Should tell you where your power is supposed to come from. Start at E5-6 IAW identification table and trace it to find relay trigger.
Hope you find your solution

 

I cant get that page to load

 

all of these are off that link

 

Any other suggestions

 

There is a ceramic resistor for the pump on the drivers inner fender there by the air cleaner. Bat voltage comes in the front, and a few volts less goes out the rear, directly to the pump. It's mostly to quiet the thing. You can bypass or eliminate it if you want. You might check that.

 

Test light check for power to pump at tank it will only run for a couple of seconds have some one cycle key while probing wires .

 

Is it possible to be an ignition switch or computer

 

What are your symptoms? How do you know your fuel pump isn't coming on?

 

Cause i always here it run when i turn the key on now it wont start got no fuel pressure and if i ground one of the tabs on the test port for the ecu it will turn on it ran but i pressure washed the engine bay it wouldnt start up and thats when i found out the pump wont comming on

 

You said it stopped running after you pressure washed the engine bay?

 

Ya gotta start testing from pump work backwards theres not a over the net fix with out testing ....

 

That's what he said. SMH.

Good luck, Sparky.

 

I checked fuses and relays i changed the ignition switch but on the computer there is the L shaped data test port and if i ground top right prong with the key on the pump will come on but i also checked and i do not have fire either could this be the computer bad or is there a way to test the computer