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Unread 05-30-2013, 10:18 PM   #16
Glasssplinter
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1994 ZJ 
 
Join Date: Sep 2010
Location: Farmington
Posts: 192
Quote:
Originally Posted by Yttrium View Post
Yes I install the pump a few weeks ago, I've check the volts n everything, for the relay fuse box, there's power but somewhere past it the wires are shot. I checked the plug by the fuel pump the female one n there's not even power coming from there, or the wires behind it. So somewhere, the wires have gone bad I guess, I'm about fed up with it. Today I almost to a sledge hammer to the jeep. I even hooked a wire up to the relay n ran it to the new pump n still no power. I'm about to take it to a shop because I'm completely lost with everything. Thnk you everyone for your help I wish this was something easy.
Something isn't adding up here with the pump. If you have voltage at the relay and ran a wire straight off of that to the pump you should be working. Assuming that you still had the positive coming off the relay try running a new ground from the pump to the body and see if it runs.

Another option is to check continuity between the relay socket and the pump to see if the wire is actually broken. Then check the other pin in the harness to make sure the ground is good.

Don't give up on it yet, you've got power at the box which is the hardest part down. Now you just need to trace the wire in between and see where the break is. Could be as simple as the connection at the relay connection.

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Unread 05-31-2013, 11:37 AM   #17
ZJNewbi3
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Join Date: Mar 2013
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Sadly I'm not positive. I checked all the sensors and found power at them all, had.no power at the jeep end of the pump connector but the pump ran fine. Replaced the PCM, still nothing. Ended up finding a blown fuse in the engine bay box (after checking it many times) replaced it and it started right up. I think my old pcm had something to do with it but I'm not sure and don't want to put it back in to test :P
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Unread 05-31-2013, 02:52 PM   #18
Yttrium
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Damn well it's leading up to something I just ripped my whole floor apart following these cords the baby blue n black cord goes under the steering wheel, in a plug along with the brown n yellow. So I guess that has something to do with the sending unit wires or something not really sure the bigger green n white goes out the firewall n wraps around the whole front of the car right up to the relay but its a neg charge wire. So the wires seem fine, I followed the solid black wire it went the other way on the passenger side up there n grounded next to the battery. So I'm thinking like where the **** is a positive wire? The orange wire that comes out of the relay not so easy to follow because how tight thg spot is n there's 5 over orange wires. So stupid, but somewhere that has to connect to one of the wires that plug in under the steering wheel? Since thos are the only cords the run to there besides the green n white n the black. Idk I'm lost yet again n confused. Haha
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Unread 05-31-2013, 09:06 PM   #19
Yttrium
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Okay I'm doing good right now I was talking with my dads friend n he told me to hot wire it from the ignition wire n I did n the pump finally has power n there's fuel flowing threw to the rail n there's pressure but the car isn't starting all the way, it says my tank is empty when it's not, so it's dark out n I went out there n did this so I'm happy for the night when it's light out I hope i can figure it all the way out! Because tmw will be Saturday n I wanna go mudding!!! Thank you everyone for everything, so lets hope I can figure out why it's saying empty but power is running to the pump tomorrow)))))))
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Unread 06-01-2013, 03:44 PM   #20
Yttrium
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Well now I'm stumped yet again, I have power to the pump, the fuel is flowing threw the line to the rail. But the jeep still isn't starting, on top of it, it's saying on the gage I have no fuel n it's empty. Well it should be starting since there is fuel in the rail. I even tried jumping the jeep n still no start. I dropped the tank again n checked all the wires on the pump, all good. So now I have no clue, so is there something else wrong with my jeep........so yeah :/
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Unread 06-01-2013, 04:05 PM   #21
Oldfrog
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1997 ZJ 
 
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Check these :

1. ALL fuses in the PDC ( fuse box under the hood). There is one in there that blows if the downstream o2 sensor wires short. If it has blown, before replacing it, check the wiring to the O2 sensor at the cat. It likes to rub and short to the frame...or even wrap around the drive shaft. Fix the short before replacing the fuse.

2. In the same fuse box under the hood, there are a bunch of black relays. Make sure your horn works, and if it does, swap the horn relay with the ASD relay.

3. Next thing, I would wiggle the connector plugs on the PCM ( computer on passenger side firewall, behind the coolant bottle). Then try again to start it.

Do that much and report to us what happened. Sounds like a no spark condition. Oh, also....tell us if you have an alarm system. If so, lock and unlock your rear hatch with a key. Then try to start it.

If still nothing works, I'd be looking at battery grounds, coil grounds, cam sensor ( under distributor cap), crank sensor, etc.
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Unread 06-01-2013, 06:54 PM   #22
ZeeJay1997
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When you turn the key on, does the check engine light come on for 3 seconds? If not, PCM is dead.

If the PCM is dead, and PCM fuse is good (the one OldFrog is talking about) disconnect O2 sensors and see if that helps. If no help there, disconnect crank sensor and see if you get fuel gauge working again. it wont crank, but there is a failure mode of the crank sensor that will kill the PCM without blowing a fuse. It wont crank with crank sensor disconnected, but everything else should work, including the 3 second buld checl i was talking about earlier.

three gallons of fuel is not enough to register on the needle. Put at least 5 in.

Read this in your spare time...http://www.jeepforum.com/forum/f13/1...23/?highlight=

Hope this helps.
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Unread 06-01-2013, 10:56 PM   #23
Yttrium
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Join Date: Mar 2013
Location: Boyne City, MI
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Awesome guys you just made me have more hope for the gal, I'm not home right now, ill be there tmw n I'm doing everything y'all talked about, thank you guys I've been getting so stressed over this I miss driving my jeep. Ill get back to you guys tmw after mess with everything! Thank you very much.
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Unread 06-03-2013, 09:00 AM   #24
Yttrium
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Well I went out there n I wanted to check to see of the cel came on, nothing it won't come on. I unplugged the o2 sensor still nothing I took my PCM out n it's competelty rusted n corroded. So could this be the problem in the jeep all along? Where would be. Good place to buy one ready to go for me? Can ebay be trusted with them, loaded with my miles n everything?
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Unread 06-03-2013, 12:01 PM   #25
Oldfrog
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1997 ZJ 
 
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The PCM case being dirty doesnt indicate a bad PCM. Did you disconnect the battery cables before you removed it ? I hope so. But since you have it out, spray some electrical contact cleaner on the connector pins and the sockets to clean them up. Apply a TINY amount of dielectric grease over the connector sockets and reinstall it.

People have had spotty results from buying PCMs on ebay...or from any of those outfits in Florida. Buyer beware. But there is no reason yet to buy a new PCM. If you get to that point, get it from Kolak, here on JF, or buy a Cardone brand from Oreilly's, etc.
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"..it's not air, it is the opposite of air... suckage so to speak."

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Unread 06-03-2013, 01:37 PM   #26
Yttrium
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Now that I think of it, I don't think I did. What could that lead too? Completely ****ing the computer up? Yeah I'll do that to the pcm the engine light isn't coming on when I turn the key over. But like you Said it could be a plug not in correctly or build up on the bolt holders.
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Unread 06-03-2013, 02:41 PM   #27
lipskid
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You say your fuel gauge is on empty even tho you have a full tank?
Try unplugging your crank position sensor (on top of the trans drivers side)
if your gauges come back thats your problem, had this very thing happen to me with my 98 ZJ.
ok so it breaks down like this, Jeep decided to tie the fuel pump and igniton and all the gauges into the crank position sensor.
if all the gauges are dead (not moving with ignition on) then the sensor can be the whole problem, try unplugging the sensor turn your ignition back on and see if all your gauges come back on ( voltage,fuel etc...) if they do then you have found your culprit. its an easy repair and the part is cheap too! hope that helps!

Last edited by lipskid; 06-03-2013 at 03:02 PM..
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Unread 06-03-2013, 04:04 PM   #28
ZJNewbi3
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Bought my PCM from rockauto and it works great
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Unread 06-03-2013, 04:19 PM   #29
Yttrium
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Yes lip, I just cleaned up my pcm plugged everything in all nice, went to see if the the Gage's work/cel would come on nope nothing turned it off n unplugged the CPS from the plug not where it goes in because that's a ***** to do. Still doing the same, I've notice with my ground that goes to the fender it's completely covered on green corroded stuff, it's all the way threw the wire, could this be my problem? Maybe. Or maybe it's that n the pcm is dead n jeeps are getting stupid haha
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Unread 06-03-2013, 04:20 PM   #30
Yttrium
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Yes rockauto is awesome that's where I got my fuel pump from.
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