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Old 05-18-2008, 01:52 PM   #1
Join Date: May 2008
Posts: 1
Starting Problems

I have a 91 Jeep Wrangler (4.0). I was moving slowly in 4wd and the motor quit. I tried to restart, but the starter engages but does not start. It's like its starving for fuel.

-I checked the fuel rail by depressing the valve stem and it sprayed fuel.
-I checked the coil, it has spark.
-I checked the engine codes and it showed 42, which is 1)automatic shutdown relay circuit, 2)fuel pump relay circuit, 3)fuel level unit, 4)z1 voltage missing when autoshutdown circuit energized.
-I poured a little gas in the throttle body and it wanted to start but didn't
-I do not hear the fuel pump running with the key switched
-I then checked power out of the fuel relay circuit and have no power. I switched relays with known good and still did not have power. I disconnected the fuel pump at the tank, jumpered the relay, and have power. But then when I connect the fuel pump back at the tank, the fuel pump does not come on and then I hear the automatic shutdown relay click.
-I did hook 12v straight to the fuel pump and it came on.

Anyone have any ideas? Could it be my fuel pump is indeed bad and drawing too many amps or something in this automatic shutdown circuit?

Thanks for any help!

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Old 05-18-2008, 05:28 PM   #2
jpdocdave's Avatar
Join Date: Mar 2008
Location: beach park, il
Posts: 8,162
fun one. i doubt pump is bad, if you give it power and it runs the pump, then its good. some reason pump isn't getting power, and obvioiusly not relay. i can't remember if there's a fuse or not. checkem all anyway.

maybe check a wiring diagram for where pump is getting power along the way. good luck and let us know

oh yeah, welcome to wf.
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