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Old 11-01-2012, 01:20 PM   #1
Join Date: Nov 2012
Location: Catharpin, VA
Posts: 3
Fuel Pump / Ignition Issue

Problem is worse when fall temperatures drop.

Jeep will not turn over until check-engine light comes on, a clicking noise engages in the elctrical box, and the fuel pump turns on. During the summer, this is only a 1-2 second delay. During the winter, I turn the iginition on, but don't crank it over and it can take up to 10 minutes before the check-engine light comes on, at which point she cranks over. Clearly the fuel pump isn't kicking in, but why only when it's cold? I've already replaced the fuel pump relay. No difference.

Anyone else experience this?

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Old 11-02-2012, 12:37 AM   #2

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Join Date: Apr 2012
Location: North Las Vegas
Posts: 9,661
So it is weather related which is a change in temperature and how about humidity? Since everything that is metal shrinks in cold weather there is the question. I would say a connection somewhere is corroded or just not tight. So it is going to be chase the needle in the haystack time which really sucks. So if you have a wiring diagram you are going to have to start checking at the beginning of what starts the ignition circuit. Here is the ignition circuit for a 93 shoulod be current with yours I hope. And I hate to say this but have you ever replaced the ECU? or done the capacitor change??? comes to mind but I would check all the simple stuff first.
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Old 11-02-2012, 01:26 PM   #3
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Location: Central Alabama
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classic symptom of the ECM going bad......
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Old 11-02-2012, 02:52 PM   #4
Join Date: Nov 2012
Location: Catharpin, VA
Posts: 3
I'm hoping it's the wiring, but wouldn't be surprised if its ECM unit. Thanks.
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