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not getting full 12v at coil

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Old 03-09-2014, 10:42 PM
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Default not getting full 12v at coil

I have a 95 ext. cab 4x4 dak with 3.9, I drove truck into the garage and thats where it still sits 2weeks later, I replace the timing chain and tensioner got it all back together and now it wont start, I noticed that i didnt hear the fuel pump kick on when i turn the key on, so I got online and was reading about the splice issues, checked them they are good, then I went to the power distribution box swapped the starter and fuel pump relays same results then swapped the auto shut down relay, same results, then I was reading about crank/camshaft sensors so I checked for spark and I am not getting any, but when I check the voltage at the coil connector it fluxuates between 6.5 and 4.3volts on both wires, I thought it should be at 12 volts but could be wrong. Went on to the computer out on the pass side inner fender and didnt really know what to start with there but what I found was if I unplug the computer and plug it back in the first time I turn the key on the fuel pump kicks on but will not kick the 2nd time and so on. Suggestions Please. Thanks
 
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Old 03-10-2014, 12:28 AM
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Are the relays working? Take off the cover on them and physically verify they are working.
 
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Old 03-10-2014, 07:05 PM
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i popped the caps off and when i turn the key on they don't move. If I force them to make contact I can hear the fuel pump turn on and I can hear a clicking when I make the auto shut down connection.
 
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Old 03-10-2014, 08:47 PM
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I have been reading that if your check engine light doesn't come on when you turn the key on that the computer is done for, is that correct?
 
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Old 03-11-2014, 07:42 PM
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By you not having the relays work when you turn the key, (but the pump works when you phyislcy move it), means you're not getting power to them from the key. It still sounds like the notorious splice to me, or a bad ignition switch, does the radio work when you turn the key on?
 
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Old 03-12-2014, 11:06 AM
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Crazy Thanks for trying to help me get back on the road. You are talking about the red\white splice, correct? I guess it doesnt really cost anything to redo the splice. Can you verify that I am at the right splice? Thanks again
 
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Old 03-13-2014, 10:41 PM
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Alright, I went ahead and redone all the splices I am getting voltage through the red/white wire, and when the key is on I get voltage through a dark blue wire. While redoing the splices I found that there is a splice that has blue/yel wires and I hooked a test light from the ground to it and when the key is on the asd relay functions on its own. Anyone have a wiring schematic? I am leaning toward ground issue now, any suggestions or thoughts? Thanks
 
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Old 03-13-2014, 11:09 PM
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There are wiring diagrams in the service manual free to download in the FAQ in this section (just a few posts above this one).
 
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Old 03-15-2014, 10:44 PM
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Well I got the truck back up and running, when I reinstalled the alternator I didn't hook both ground wires back up so the computer ground was tucked under the alternator and I couldnt see it, I got it hooked and it fired right up to hear a lifter noise ( man was I p*ssed) so back apart it came and I found some little bearing pins just laying in the valley (Just great). Is there any tricks to pulling the lifters without having to remove the heads?
 



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