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Old 05-30-2004, 02:37 PM
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Default Dead Fuel Pump or just a relay???

Today I went to bring my 911 back from my mom's where I stored it while on vacation. After the usual "haven't been driven in a while" puff of smoke dissapated, I moved the car about 3 feet and let it idle a couple more minutes. All of the sudden, the car sputtered out and died. I couldn't get it restarted. Here's what I know:

- It seems to crank fine.
- I opened up the airbox and pushed up the thingy and got the clicking sound (but don't know why I did this step)
- If the engine is off and the key is in the 2nd position (just before "start" I don't seem to hear a sound from the front of the car like I used to leading me to think it was the Fuel Pump.

I know you can "jump" the relay or the fuse panel, to test the FP, but I can't recall which posts/points to test on (Pari, can you tell me again??? ).

Many Many thanks! (as usual!)
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Old 05-30-2004, 02:46 PM
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Steve, do you have a voltmeter? If so, you can check for power to the fuel pump as your first troubleshooting step. Let us know what you find out.
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Old 05-30-2004, 03:00 PM
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Quote:
Originally Posted by Jim Richards
Steve, do you have a voltmeter? If so, you can check for power to the fuel pump as your first troubleshooting step. Let us know what you find out.
Yes I do. Unfortunately, the car is in Falls Church and I'm in Arlington. I can't test it until manana at best Assuming I get less than 12V, it's the relay, right?
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Old 05-30-2004, 05:00 PM
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Jump pin 30 to 87a. That puts 12v directly to the pump. You should hear it run. If you are in luck the pump will fail hard. Bad luck is if it goes intermittent before you can check other things. Check valve, accumulator come to mind. Another test, pull one injector and put the key in the run position, push up the thingie and if you have a dribble of fuel you have a working pump.
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Old 05-30-2004, 06:34 PM
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Steve, you can pick up some test leads(the wires with the alligator clips) at Pep boys for a buck. Then remove the red fuel pump relay, and connect one end of the wire to the fuse for the fuel pump, and the other end onto the fuel pump relay.

After doing this, you should be able to hear the fuel pump turn on. If you hear nothing, then your fuel pump is dead. If you do the above test, and hear your fuel pump running, then it is likely you have a bad fuel pump relay or relay socket.
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Old 05-30-2004, 08:35 PM
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Quote:
Originally Posted by Parenn911
Steve, you can pick up some test leads(the wires with the alligator clips) at Pep boys for a buck. Then remove the red fuel pump relay, and connect one end of the wire to the fuse for the fuel pump, and the other end onto the fuel pump relay.

After doing this, you should be able to hear the fuel pump turn on. If you hear nothing, then your fuel pump is dead. If you do the above test, and hear your fuel pump running, then it is likely you have a bad fuel pump relay or relay socket.
Got the leads. I will be trying this tommorow. Assuming you pulled the red one for the fuel pump, why is there still a red one plugged in?
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Old 05-30-2004, 11:26 PM
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Quote:
Assuming you pulled the red one for the fuel pump, why is there still a red one plugged in?
Steve, I bought a bunch of red relays from pelican(notice the "made in China") and used them in place of some of the black ones. Most SC's with the stock set up have only one red relay for the fuel pump, and the rest black.
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Old 05-31-2004, 09:57 AM
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It appears that the relay is the problem. I jumped from #30 to the fuse block with the key in the "off" position. Kinda scared me!!! But glad I heard the pump running. Isn't it ironic, I have the whole day to work on the car and the dealer (or Porsche shops) aren't open to sell me one. Oh well, it's a lousy rainy day..
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Old 05-31-2004, 12:37 PM
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Good thing it wasn't the pump. It should be a cheap fix with a new relay or relay socket, both parts are around 20 bucks.
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Old 06-01-2004, 10:12 AM
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Pari, you mentioned a relay socket for $20.
I had a problem with my socket and couldn't find the exact one for the fuel pump. I think it's part of the harness. Did you find a fuel pump relay socket?
Good news Steve.
Did you move yet?
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