help 944 no power to fuel pump
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it mite be in the book/Manuel somewhere and I am just missing it , at this point who knows
I need some help pointing me in the right direction
I got the gas tank replaced in my 1984 non-turbo Porsche 944 I had previously replaced the tank screen and fuel pump a month or so ago and put on new fuel filter the other day but when I got it back together it test drove ok then died after about 10-12 miles more and would not restart so I trailered it home ...again... I though the screen was clogged again blocking fuel but no has good fuel flow so next I pulled the new pump out to test works good , ok next I turn key on and test power wires that hook to fuel pump .....no power I figured great now I know what the problem is and how to fix it but that was wishful thinking
ok so now I look at both fuse boards no blown fuses and with key on if there is power at one side there is power at the other side of each fuse there are about six with no power at all when I tested but fuses are not blown
is there any other fuses that would effect the power to the fuel pump or a diagram showing exactly which fuse powers the fuel pump ?
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I got the gas tank replaced in my 1984 non-turbo Porsche 944 I had previously replaced the tank screen and fuel pump a month or so ago and put on new fuel filter the other day but when I got it back together it test drove ok then died after about 10-12 miles more and would not restart so I trailered it home ...again... I though the screen was clogged again blocking fuel but no has good fuel flow so next I pulled the new pump out to test works good , ok next I turn key on and test power wires that hook to fuel pump .....no power I figured great now I know what the problem is and how to fix it but that was wishful thinking
![crying](https://rennlist.com/forums/graemlins/bigcry.gif)
ok so now I look at both fuse boards no blown fuses and with key on if there is power at one side there is power at the other side of each fuse there are about six with no power at all when I tested but fuses are not blown
is there any other fuses that would effect the power to the fuel pump or a diagram showing exactly which fuse powers the fuel pump ?
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ok still need help
took out the DME fuel pump relay 993.615.227.00 I tried the jumper wire on number 2 and 8 (30 and 87 on the 924's) still don't have power at the fuel pump ...................... NOW WHAT SHOULD I CHECK NEXT ?????????????
which one is the o2 sensor fuse ?
took out the DME fuel pump relay 993.615.227.00 I tried the jumper wire on number 2 and 8 (30 and 87 on the 924's) still don't have power at the fuel pump ...................... NOW WHAT SHOULD I CHECK NEXT ?????????????
which one is the o2 sensor fuse ?
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and I can put a test light in the jumper wire and have power so what is between the relay panel and the pump that could cut the power going to the pump form the relay????
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I have traced the wires form the pump at the back up along the bottom of the door then lose them behind the side and in the jumbal of wires behind the fuse panel , I have the fuel pump relay out and a jump wire in and have power at that point but not at the pump, the aux fuse panel #2 fuel pump fuse is good .
at this point I am assuming that some where between the wiring harness running along the drivers door bottom and the fuse panel there is a short or cut ................. is that a straight wire or is there any connection in there? I already have the broken hood latch handle and truck button out but How do I get the drivers side bottom front carpet part off so I can look for damaged wires?
at this point I am assuming that some where between the wiring harness running along the drivers door bottom and the fuse panel there is a short or cut ................. is that a straight wire or is there any connection in there? I already have the broken hood latch handle and truck button out but How do I get the drivers side bottom front carpet part off so I can look for damaged wires?
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The carpet is tucked underneath the door trim rail. It will lift right out and the harness runs from the relay to the drivers side firewall area, mixes in with a bigger bundle, and then runs along the floor pan past the drivers seat, up over the wheel well, and then to the middle of the hatch area up top and there is a hole there for the wire to drop through to go to the pump. SO
The wires to the fuel pump go directly from the relay to the pump, no breaks, and no plugs IIRC. So if you jumper the relay correctly - (double check that you have!) - you should absolutely get 12V out to the fuel pump wires. Again IIRC, the fuel pump doesn't kick on till you start cranking the motor.
The wires to the fuel pump go directly from the relay to the pump, no breaks, and no plugs IIRC. So if you jumper the relay correctly - (double check that you have!) - you should absolutely get 12V out to the fuel pump wires. Again IIRC, the fuel pump doesn't kick on till you start cranking the motor.
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ok I did not realize the pump did not start until the key was cranking position instead of just the on position ........ but I have tried both was to start car. So there is no wire connection type plugs between the fuse panel and the wiring bundle going under the door..........hummmmmm......... going to try pulling that carpet anyway just to check nothing got cut somehow other wise I am at a loss on how to fix it
"So if you jumper the relay correctly - (double check that you have!)" I have double checked my double checking ...lol
"So if you jumper the relay correctly - (double check that you have!)" I have double checked my double checking ...lol
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I have the jumper wire hooked up correct and it has power to both sides of the jumper but then somewhere in the bundle behind the panel or in the side before it gets to the drivers door heading towards the back I lose the power . I have tried to pull the fuse panel out so I can see behind it but it does not come out very far
no I have not specifically checked the 02 fuse cause I am not sure which one it is , but all fuses on main and aux panels are good (none blown)
no I have not specifically checked the 02 fuse cause I am not sure which one it is , but all fuses on main and aux panels are good (none blown)
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ok just got some of the carpet off doesn't look like any nicks or cuts in the wire there either. but now the #2 fuse on the aux panel for the fuel pump does Not have power but it did earlier???????? I tried with key off and on and jumper wire is still pumped in instead of relay (do have power at jumper wire)
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I feel kinda stupid now who would have guessed that two fuse panels for safety was not enough ![Roll Eyes (Sarcastic)](https://rennlist.com/forums/images/smilies/rolleyes.gif)
I just found it , now someone please tell me what the proper name is so I can order one
it has three red wires and one brown wire that run form the aux fuse panel back up under the dash to a leather pouch that is holding a small square plastic box with four prongs, one of the red wires is hot but the other red wire that runs to aux fuse panel fuse #2 for fuel pump is not hot but if I pull that wire off and jump it on the hot wire I can hear the fuel pump run
. There is NO parts numbers on this black box it only have 12V 30A stamped on top what is the proper name for this part so i can get one ????????????????
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![Roll Eyes (Sarcastic)](https://rennlist.com/forums/images/smilies/rolleyes.gif)
I just found it , now someone please tell me what the proper name is so I can order one
![bowdown](https://rennlist.com/forums/graemlins/bowdown.gif)
![jumper](https://rennlist.com/forums/graemlins/jumper.gif)
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