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Discussion Starter #1
So I bought a car 1994 Nissan Altima that's been sitting for year guy said bad fuel pump got new and changed not getting power to it I have power at the relay but not to pump please help
 

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09 Altima 3.5SE 6MT Sedan
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You can jumper the relay load terminals temporarily to see if the pump works, but as amc49 said, a lot of other things have to go right before the ECU will tell that relay to turn on.
 

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Discussion Starter #4
My pump is good cause I have direct power I can hear so what do I do just jumper wire which two terminal at relay socket and pump should work Im think my ECU is not working properly I just bought the car and it's been sitting 3 years the first thing I did was change the fuel pump and all the fuel in the tank like I said I have power at my relay but not back to the pump
 

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09 Altima 3.5SE 6MT Sedan
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There's a good chance of a lot of corrosion in the fuel system...if it sat for 3years with 10% ethanol in it. Start with the basics, crank, fire, fuel, air...
 

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Discussion Starter #6
My pump is good cause I have direct power I can hear so what do I do just jumper wire which two terminal at relay socket and pump should work Im think my ECU is not working properly I just bought the car and it's been sitting 3 years the first thing I did was change the fuel pump and all the fuel in the tank like I said I have power at my relay but not back to the pump
There's a good chance of a lot of corrosion in the fuel system...if it sat for 3years with 10% ethanol in it. Start with the basics, crank, fire, fuel, air...
well if I spray it with starting fluid it will crank and run I hook the battery directly to another car battery and started the car just to circulate the antifreeze and everything in the car runs great I just don't have power to the fuel pump like I said earlier I drain the tank as well as put a brand new fuel pump brand new fuel filter brand new plugs and new wires
 

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I for one am backing off here as simply trying to jump the relay incorrectly can backfeed into ECM to scrap it if done wrong and if it wasn't bad you may easily make it so.
 

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09 Altima 3.5SE 6MT Sedan
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Do you know if the relay is good...ie if the winding is open cct (burnt) it won't work or if the load contacts are all carboned up it won't work either? Try swapping it with a similar unit from elsewhere or the scrap yard.
 

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Discussion Starter #10
I did that that was my first guess I actually have the same exact car same color and all lol only difference is one is auto and other manual
 

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09 Altima 3.5SE 6MT Sedan
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Ok, how about taking the non-working car's ECU and installing it temporarily in your working car? If only to see if the fuel pump spins up or not? You can decide if you want to go further than that with it (ie attempt a start).

I wouldn't suggest going the other way in case you have coils or solenoids or whatever that are straight shorts...wouldn't be good to kill the working ECU...
 

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Ok, how about taking the non-working car's ECU and installing it temporarily in your working car? If only to see if the fuel pump spins up or not? You can decide if you want to go further than that with it (ie attempt a start).

I wouldn't suggest going the other way in case you have coils or solenoids or whatever that are straight shorts...wouldn't be good to kill the working ECU...
Can you text me 912 237 2058
 

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09 Altima 3.5SE 6MT Sedan
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It might get upset about minor things like speed, traction control, abs and of course the keys/security...none of which you care particularly about..you just want to see the pump work as expected. Depending how sophisticated the security system is, you may have difficult starting if you go that far...to avoid this, wrap the car key plastic portion (contains transponder) in tin foil, and put the matching key for the ECU in proximity to the keyswitch on the column.
 

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Discussion Starter #15
It might get upset about minor things like speed, traction control, abs and of course the keys/security...none of which you care particularly about..you just want to see the pump work as expected. Depending how sophisticated the security system is, you may have difficult starting if you go that far...to avoid this, wrap the car key plastic portion (contains transponder) in tin foil, and put the matching key for the ECU in proximity to the keyswitch on the column.
I think imma just plug it in and see if the pump kicks on that will tell me my computer no good
 

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09 Altima 3.5SE 6MT Sedan
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and make sure you disconnect the battery before removing, and reconnect after everything is attached...you don't want to blow that ECU up :)
 

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Discussion Starter #17
and make sure you disconnect the battery before removing, and reconnect after everything is attached...you don't want to blow that ECU up :)
D0ugmac1 do you think that's where my problem is going to lie at in the ECU and it's behind the center console right under radio correct so as long as I don't start the car I should be ok just to hear my fuel pump run then go to junk yard or eBay and buy a ecu for 94 Altima manual trans and does it have to be programmed or no
 

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09 Altima 3.5SE 6MT Sedan
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I'm not familiar with '94's. I would be surprised if the ECU is inside the car...on my Gen3 and Gen4's it's been beside the battery...if it is a PITA to get at...then we find another way to test.
 

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Has anybody done something as simple as removing the pump relay cover to manually move the switchplate with a finger to on with somebody else turning key to start?

Getting all crazy and yanking ECM too early if you ask me, they can damage simply from static in your fingers if you are unlucky that day. You don't mess with ECM UNTIL you have exhausted ALL relay location possibilites. The wiring from relay to pump has not been proven out either if I'm reading that right.

ECM damage is most commonly done by those that never should have even been there yet. You ALWAYS pursue that ONLY as the last resort, it can save hundreds of $$$$$$$$$. It's insane to risk that without being 100% sure a thirty cent run of wire is working right first.
 
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