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83 Fuel pump no power

ive been troubleshooting a no start condition on my 83 and found that the fuel pump is not receiving power even with the relay jumped. however when i put my hand on the pump it is noticeably hot. what would be the cause of this? just a bad pump?

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1983 944 Guards Red (87' Implant Complete)
Old 07-11-2009, 05:43 PM
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Hi, if your pump is getting hot seems to me that it is getting voltage. I would have a buddy crank the motor over and while he is cranking you put a volt meter on the 2 leads going to the pump itself and see if you are getting voltage to it. 12 volts to fuel pump will only be present when car is turned over not when key is just turned on.
Old 07-11-2009, 06:24 PM
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it should be getting 12v from the leads at all times when jumped though shouldnt it? i tested for the 12v from the green wire on the fuel pump. i also dont hear it humm when the key is turned like it normally should to prime the system
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Old 07-11-2009, 06:43 PM
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Hi, yes the relay should be getting 12 volts when jumped to the fuel pump. The reason that I think it could be geting voltage is that your pump is hot? Hot pump means voltage and no turn? You will only get 12 volts normally to pump when you crank the starter over. It is a safety feature. You won't get 12 volts with just the key on to pump unless the wiring has been changed by someone in the past?
Old 07-11-2009, 06:54 PM
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Look for a burned contact at the back of the fuse block. The fuel pump contact is very susceptible to that problem.
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Old 07-12-2009, 04:10 AM
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Quote:
Originally Posted by 944 Ecology View Post
Look for a burned contact at the back of the fuse block. The fuel pump contact is very susceptible to that problem.
ill do that when i get home today.

how would i bypass a aftermarket alarm thats designed to cut power to the DME/Fuel Relay. im thinkin mayb that is the cause since it has sat for so long not plugged in and in the vegas heat mayb it is faulty now.
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Old 07-13-2009, 11:48 AM
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Hi, you are going to have to trace your aftermarket alarm wires and disable them one by one.
Old 07-13-2009, 01:18 PM
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Originally Posted by zedsn View Post
Hi, you are going to have to trace your aftermarket alarm wires and disable them one by one.
ugh, i really dont enjoy tracing wires in the car. i gotta trace the power window wires too since my passenger side doesnt work
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Old 07-13-2009, 01:56 PM
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aftermarket alarms are aftermarket alarms and wirings vary I would think.
Old 07-13-2009, 02:13 PM
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I would put my money on a clogged fuel pump. run a jumper line from the battery to the pump, and if you don't hear the little guy hmmmm it's the pump.
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Old 07-13-2009, 02:40 PM
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checked the back of the fuse panel, no scarring on it though the fuse was toast from bein jumped to long. also cehcked for voltage to the pump while bein cranked over, it received 10 on first turn of key then it jumped up to 12-13 for the rest of the turn over.

if i pull the pump how would i go about looking to see if its clogged? or should i not bother and just replace it.
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Old 07-13-2009, 07:56 PM
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It could be the fuel pump check valve is froze up. It is located on the out flow side of the pump, between pump and fuel filter. If frozen it can ruin the pump. Tap it several times and it might free up the valve.

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Old 07-13-2009, 08:44 PM
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I would just replace the pump and make sure your tank is clean inside. After you drain the tank you can pull the sending unit in the trunk area and inspect your tank. Or you could do it with fuel in there as well. A dirty tank will wipe out a new pump in no time.
Old 07-14-2009, 04:02 AM
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the tank is pretty clean, when i emptied the fuel out before putting new stuff in it came out just as clean as the stuff i put in. ill check out the valve when i get home, im a little hesitant to pinch that hose though as there's signs of cracking on the outside and my face doesnt like gasoline haha.

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Old 07-14-2009, 10:26 AM
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