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Discussion Starter #1
Was cruising along just fine when engine just died. Cranks over just fine, but won't fire. Only lights I get on dash are Check Engine and the Shift Light, both on constant. Tried pulling codes (using the 3x ignition on/off), but I get absolutely nothing from that. Both lights still on constant. Must've tried that 15 damned times praying she'd give just a little hint.

Managed to get one of the fuel lines pulled from the rail and at first it seemed dry but then fuel came out plenty. Couldn't get other one to budge. Checked pressure valve on fuel rail and she's a squirting. On a whim I checked the fuse box by the battery an first one I pulled was Fuel ECU....blown. Stole the other 30A one from the headlight system and tried cranking it....blown.

Started poking around at any obvious connections to the fuel system and thought I got "lucky" when I wiggled the TPS and the housing snapped right in half and it seemed like what was supposed to be a wire terminal was stuck on one of the 3 posts in the half that came off. Borrowed friend's car to run around getting parts and get back to my poor lonely Jeep on the side of I73. Of COURSE thunderstorm from hell hits just as I get back to it so waited that out....well at least the worst of it. Installed new TPS, replaced 30A ECU fuse, cranked it...nothing. Just another blown fuse. (And unfortunately friend needs his car back today)

There is obviously a dead short somewhere (or the entire ECU is fried), but anyone have any pointers where to start poking? Only managed to grab 4 extra 30A MAX fuses from the store (cleaned them out) so I do get at least a few chances at this, but don't feel too warm and fuzzy only having 3 spares.


This all of course happens while my wife is out of town for 3 weeks and the Jeep is my only vehicle. Kinda need it a bit to get the kids to and from school and silly little things like that. I really, REALLY do NOT want to have to call Enterprise in the morning...
 

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Check to see if o2 sensor is damaged or shorted also fuel pump relay on fire wall, disconnect before installing replacement fuse no blow then maybe relay....look for wires that have open insulation where they are rubbing against ground that is most likely the cause
 

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ALLMUDD is right some quick research leads to ECU fail....good luck and let us know what the fix was!
 

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Discussion Starter #6
It is looking like the ECU unfortunately. Disconnected Fuel pump at the tank, did a quick check on the wires and no short, ignition on....fuse still good, cranked it a few times....fuse popped.

Guess I'm pulling that next and at least checking the caps. Hoping to be able to rig this without getting a new ECU.
 

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Discussion Starter #8
Well I dodged a bullet on this one. Was JUST about to rip into the ECU and decided to do a quick recheck of the wiring.

The heatshrink that was covering a wire splice on the O2 sensor had disintegrated (oil leak from the valve cover) and was a dead short. Plugged the ECU in, moved the wire off the chassis, and she fired right up. Well....fired up an died, but ran MUCH better once I remembered to reconnect the fuel pump.:atomic:

Thanks for all the input everyone. I meant to check the O2 sensor before anything else, but got distracted and sucked into tracing wires and forgot all about it.
 
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