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Intermittently dies while driving, like someone just turned key off! Turns over and may start again after a few minutes to a few days! Replaced fuel pump, fuel filter and fuel relay. Also, brand new MOPAR crankshaft position sensor. Ran great for several days, then died on the road again. Took several key turns before I hear fuel pump kick on and it started up and got me home. No MIL, no codes shown. Afraid to drive it anywhere now! Any ideas on what to do next? I can't keep throwing parts into it hoping that I'll hit on the problem.
 

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The beast from Brazil
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Could be a problem with the PCM, but also could be the ignition switch or wiring. Does any fault code show up?
 

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No fault codes at all. Wish it did show some codes, at least I could narrow it down then. It runs good...when it's running.
 

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The beast from Brazil
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The ground for the fuel pump to run is made inside the PCM, but the power comes via the ignition switch. This same power is used for the auto shutdown relay, so without this power the fuel pump doesn´t run, but also the ignition doesn´t work. If the problem is there, then remove the fuel pump relay or auto shutdown relay and measure between slot 86 and ground with the ignition switch in RUN. You should have 12V, if not, most probably the ignition switch is faulty, or wiring.
 

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I agree with Frango ^.
What you might try to eliminate an intermittent ignition switch is to jiggle it while the engine is running.
You probably either have a bad ground somewhere, frayed cable harness, bad ignition switch or a flakey connector or relay,
With engine and battery disconnected, try swapping the ASD and fuel pump relays with other like relays or even a new relay one at a time.

Yeah these older Jeeps are not the best for showing CELs for pinpointing problems.
 

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Discussion Starter #6
Checked ignition switch ( no problem, it kept running while it was jiggled) and just replaced ASD relay as a precaution. Did find a loose positive battery cable at the terminal, tightened it down. Drove it home with no problems but we'll see how it goes this week. Also, pretty sure I have a short in wiring for power windows, door locks and mirrors as the stopped working but all worked after driving 1/8 mile down the road. Will check them once I find the time. Just so frustrating trying to eliminate all the possible causes to this stalling/ no start issue.
 

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A loose battery clamp definitely could cause at least the engine dying problem though i'd think that usually would show up while cranking the engine but who knows.
You could be making progress. Find and take them gremlins one at a time....nothing like a good 'ol challenge at least for me.

Far as the door lock, window and mirror issue if their fuses are not blown, likely its connector somewhere.
Could also be the harness at the door jam (usually the driver's side door) might have a broken wire or two in it.
A semi common problem with older Jeeps with a lot of miles on them.
Try jiggling that harness to see if it either creates a problem or temporarily fixes the problem.

Or the window/mirror switch pod on the door could be bad. Don't know about the '03's but with earlier Jeeps this was another semi-common problem.

I had similar issues with my power windows on my XJ.
Rreplaced the window switch pod with one i bought off ebay for somewhere around $40 and its still working great after 30,000K some miles.
 

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The beast from Brazil
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The power window/lock problem is indeed most of the time a broken wire inside the rubber boot between the door and the jamb. Many times the wire insulation is still intact, making it even more difficult to discover. You will have to remove the rubber boot and lightly bend each wire to discover the broken one. The wires are too rigid and after bending many times over the years, they get brittle and break.
 

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Discussion Starter #9
Well, back to searching for answers again. Jeep did well for most of the week. Died a couple of times while at idle, started right up each time. Saturday, it died and would not restart. Left it a couple of hours, came back and it fired right up. Some are saying cam sensor, others claim it's a PCM problem. Replacing cam sensor today, if that won't do it, then PCM will be next I guess.
 

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Discussion Starter #10
Replaced the cam sensor, still same issue of dying at intermittent times. Died on my way to work, started again after several minutes and attempts. Drove it to work, started right up when I was leaving, ran for several seconds, died and would not start again. No sound of the fuel pump coming on when I turn the key and would not show any codes or the word "Done" when checking for codes. PCM?
 

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The beast from Brazil
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Did you wiggle on the ignition switch, or on the key barrel? The switch can still be faulty either way though. You didn't state which engine your jeep has. The 4.0 has a known problem of a cable loom which runs around a stud on the rear side of the head and the insulation can wear through and cause the engine to suddenly die.
 
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