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Discussion Starter #1
I have a 5.2 durango and to start I should say that I have replaced the fuel pump, tpc sensor, IAC sensor, map sensor, crank shaft sensor, new distributor and rotor, plug plug wires, new battery!
When I turn the key to on before I try and crank it the fuel relay is clicking repeadetly and you can hear the fuel pump running. Inside the cab you notice that the fuel gauge isnt registering any gas it reads empty. When I start to crank it it will just turn over no spark or doesnt catch or run. Now on occasion the fuel relay will stop clicking and the fuel gauge will work and the truck will start and run flawlessly until it either stalls or I turn it off or until the next time I fool with it and the fuel relay clicks again and back to square one. I recently checked to see if I was getting fuel pressure and at the rail with the relay clicking and the pump running I am getting 49 psi. I noticed that the key in the ignition is a real loose fit and I can pull the key out at any positioin. I have also tried to spray starting fluid down the throttle body and it turns over but doesnt try and fire at all like there is no spark. I have swapped the fuel relay with other relays in the box and it is with the same result it clicks and the fuel pump just runs. That about sums up I am at my wits end although I find the mystery fun and I have a good runing truck other than the durango I would very much like to figure out what is going on and being as though it doesnt run I cant take it to Oreilys or a mechanic with out a tow to get code pulled so any suggestions would be very helpful

Thanks
 

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Sounds like you are having a proble with your ignition system. I'd get the ignition cylinder in the column replaced since you say it is bad and go from there. Why overlook the obvious problem and spend money on everything else? Fix what you know is broken then go from there.
 

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Discussion Starter #3
Fuel pump runs continuosly

i checked the ignition switch and pullled it off looking for loose wires and as you said I am replacing the switch but I have to wait for it as I am getting from online. but the problem did not go away and the fiuel pump is still running and the relay is still clicking would you know of any problem that would make a fuel relay click like that or the fuel pump to continuously run and again there is fuel pressure at the rail so it must be recycling into the tank but none theless its running
 

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If the relay is continually clicking then there is a problem with the signal from the PCM to trigger the relay. either the PCM is confused or something. Could be ignition, could be a ground problem.
 

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The Anti-RUB
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As hskrRT mentioned, if the fuel pump relay is clicking continually then there is something wrong with the ignition circuit. It should only click once. The ignition circuit controls the coil side of the relay and the fuel pump circuit is on the switch side of the relay. That clicking you hear in the relay is the coil energizing and pulling the switch over to energize the fuel pump circuit. Something is causing the coil to energize on/off repeatedly. Probably a short somewhere or a lose connection. Since you mentioned the ignition switch being loose, I would start there. The problem may be a connection inside the switch, not a loose wire connecting to it.

Good luck...
 

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Discussion Starter #6
had a scanner hooked up

I had a scanner hooked up to the truck and it said check grounds and fuses and didnt give a code I took a voltmeter to the fuses and the ffuses that are hooked up to the o2 sensor fuse didnt read any volts yes I checked to see if the fuse was good. I think its a ground that goes to the 0s sensor were is that ground?
 

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The Anti-RUB
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Just to make sure you tested the fuse properly, you tested the fuses by touching the negative meter lead to the negative battery post and the positive meter lead to each of the metal tabs on the top of the fuse. Correct?

If the problem was between the fuse and the sensor (including the ground for the sensor) you would read constant battery voltage at the fuse. However, if the fuses aren’t getting power, as you stated, then the problem is between the fuse box and the positive battery post. Most likely a broken wire or loose connection. Good luck...
 

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Discussion Starter #8
but why???

But why or what is causing the fuel pump to run continuously further more if I take two wires and jump the auto relay the truck will try to fire but the motor doesnt realy start but it tries so I believe something is faulting the auto relay and something is causiong the fuel pump to run constitantly with the key is switched on and something is causiong the fuel realy to trip or click repeadetly when the ignition is turned on
 

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Discussion Starter #9
I have a new ignition on its way it should be here today so you can add to the list of parts and sensors Ive replaced
 

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The Anti-RUB
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But why or what is causing the fuel pump to run continuously
You have a short somewhere. Often times if you have one short, you can easily have another. Wires are bundled together in looms. If something rubs through the loom it will also rub through multiple wires inside that loom resulting in multiple bare wires and multiple wiring faults (a.k.a. breaks, shorts and/or resistance).

further more if I take two wires and jump the auto relay
Be very very careful when jumping relay pins. You could easily fry a computer or other component if you jump the wrong pins (e.g. pin 30 to pin 86 or 85).
If your talking about the auto-shutdown relay, that relay just supplies power to the fuel injectors. If you jumped pin 30 & pin 87 of the Auto-Shutdown relay, and the truck turned over then you definitely have a short. All jumping the Auto-Shutdown relay would do is energize the fuel injectors, but not necessarily make them spew fuel because they wouldn't have a ground. The injectors get their ground from the PCM.
 

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Discussion Starter #11
wire diagrahm

hey I was going to cut the wire that goes to the fuel pump at the connector I was wondering if you could tell me exaCTLY were each of the wires goes to so I can bypass the bundles and splice them either close to were they plug into or actually reconnect them near their final destinations
 

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Discussion Starter #12
fuel pump

So I disconnected the fuel pump at the connector that is at the drivers side frame by the front left tire, and the fuel pump no longer runs but the fuel relay is still clicking does that mean I have isolated the short and I dont have to worry aboout the short being further back towards the fuel tank. and as far as the ignition I do have a braand new one coming in the mail today so I will install the new ignnition and re hook up the pump connector and see if that doesnt cure the problem but I was wondering if the relay is still tripping and the connector is unplugged does that mean the short is further upstream if you will
 

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Well that means your problem isn't past that connector. I'd wait until you get the new ignition switch in and go from there. Unless you are just bored and want to tinker on the truck
 

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Discussion Starter #14
new ignition

I put the new ignition in and there is no change. I used a meter and I am getting a charge at the fuel rail and I also checked the charge to the distributor and I m getting one at the coil
 

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The Anti-RUB
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does that mean I have isolated the short and I dont have to worry aboout the short being further back towards the fuel tank.
No, it doesn’t really tell you anything other then what I already stated in my previous post. The problem isn’t on the fuel pump side of the relay. The clicking is due to the ignition side of the relay getting/losing/getting/losing power over and over again, which is flipping the switch inside the relay (causing the click) which sends power down to the fuel pump turning it on. Electrical pumps, like the fuel pump, don’t shut off like a switch. They need to spin down. So it may seem like it is running constantly if the power is being turned off/on fast enough. In other words, the problem is in the ignition circuit.

With that said, the ignition circuit is more then just the ignition switch. There is a bunch of stuff on both the positive & negative side of the relay, including the PCM, neutral safety switch, starter relay etc etc... You can narrow down which side of the relay is shorted with a volt/multi-meter.

first test the power side:
  • Set your meter to as close to 15 volts without going under
  • Unplug the fuel pump relay
  • Key On, Engine Off
  • Touch the negative meter lead to the negative battery post
  • Touch the positive meter lead into the whole where the relay’s pin 85 went. The relay should have the pin numbers printed on it for easy reference.
With everything running fine, you should get a constant 12 volts. If the voltage fluctuates, then the short is between the whole your testing & the positive battery post.

If pin 85 checks out, next test the ground side of the relay:
  • Touch the positive meter lead to the positive battery post
  • Touch the negative meter lead into the whole where the relay’s pin 86 went
With everything running fine, you should get a constant 12 volts here too. If the voltage fluctuates, then your short is between the whole your testing and the negative battery post.

The next part (finding the short in the wire) is the tricky part if you don’t have a the circuit diagrams for your year/model truck. If you don’t, or don’t know how to read it, I would advise bringing the truck to a tech who can track it down for you.

Otherwise, plug the relay back in, key on/engine off, get a small compass and hold it over the offending wire. The needle will point in the direction of current flow. In a working circuit, on the power side, the needle will point towards the relay. On the ground side it will point away from the relay. Since the voltage is fluctuating on you, so too will the current resulting in the needle bouncing a little. If the problem was on the power side, then go south. If the problem is on the ground side, then go north. Keep going up the wire until the needle turns around. The short will be between the last place the needle was pointing in the expected direction and the first place its pointing in the opposite direction.

Good luck...
 
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