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walbro 255 r34 gtt install


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changed my pump to walbro 255

after reading many people needing to cut wire and solder the walbro one, I didn't have to do it. it was a straight fit connector.

I put it in with the small filter that came with it rather than the original nissan filter

other than that no issues.

 

thought I post for people benefit

it also took me a while to find out how to get it out as I didn't want to break anything . I realised you just had to pull it up and the bracket tab will release itself.

 

 

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I did the relay, i managed to do a bit of f**k up

 

car started up ok and here is how i wired it

 

30 to power direct

86 to black/yellow from ecu

87 to black/yellow socket connecting to pump

85 to ground directly

 

 

all worked fine and worked fine but when i switches the car off, it continued to work non stop

 

re reading the au forum , i realised I had to also cut the green/white wire and use that on pin 85 which comes from ecu and then ground the pump directly

 

the forum post mentioned 85 as switched and 86 as ground but the relay writting is other way

all google results also show 85 as ground so i suppose it is AU relays that have the pair swapped around

 

can anyone eighten me on why ground from ecu is needed, my view is if the live/ switched live from 86 is disconnected after i turn the key to off position then that should close the relay but it doesn’t

 

to start with relay is off and only is energised when i turn the key but never disconnects again even if i turn ignition off

 

any ideas?

 

what would have been worst case scenario if pump kept running and i hadn’t noticed, would it have simply run until battery is dead ?

i suppose the fuel would have been returned to the tank and not stay behind injectors and blow them

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4 hours ago, drifter17a said:

I did the relay, i managed to do a bit of f**k up

 

car started up ok and here is how i wired it

 

30 to power direct

86 to black/yellow from ecu

87 to black/yellow socket connecting to pump

85 to ground directly

 

 

all worked fine and worked fine but when i switches the car off, it continued to work non stop

 

re reading the au forum , i realised I had to also cut the green/white wire and use that on pin 85 which comes from ecu and then ground the pump directly

 

the forum post mentioned 85 as switched and 86 as ground but the relay writting is other way

all google results also show 85 as ground so i suppose it is AU relays that have the pair swapped around

 

can anyone eighten me on why ground from ecu is needed, my view is if the live/ switched live from 86 is disconnected after i turn the key to off position then that should close the relay but it doesn’t

 

to start with relay is off and only is energised when i turn the key but never disconnects again even if i turn ignition off

 

any ideas?

 

what would have been worst case scenario if pump kept running and i hadn’t noticed, would it have simply run until battery is dead ?

i suppose the fuel would have been returned to the tank and not stay behind injectors and blow them

Brother, you really need to slow down and understand what you are doing before doing stuff.

Good on you for trying stuff, but if you don't understand the basics of wiring don't do it.

is there anyone in your area who can help in person? Trying to help you over the net is a long winded exercise

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If you did a search on this site you would find multiple tutorials on how to do this. I will link you to one and if you can't/won't follow it then best to go to a sparky lest you blow up your car (and yourself...natural selection in action?).

 

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12 hours ago, KiwiRS4T said:

If you did a search on this site you would find multiple tutorials on how to do this. I will link you to one and if you can't/won't follow it then best to go to a sparky lest you blow up your car (and yourself...natural selection in action?).

 

Did read this which is how i worked out i should have used ground from ecu cable rather than battery directly and can be seen from my earlier post

 

what i was curious on is why relay works if positive from ecu gets disconnected if negative is directly fed

 

rather than simply following, want to understand and asked in open forum so ....

 

if i wanted i would have paid someone 

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Issue fixed

 

it was purely due to me not using the cables from ecu for negative

 

what i had to do was cut it, from socket which connects to pump have a connection to ground and use the ecu negative for relay

 

even though i fixed it, i still don’t understand why that negative was important. I didn’t know there is also switched negative.

 

re pin 85 and 86, it doesn’t matter which one is positive / negative after through forum check

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The ecu grounds the fuel pump control wire when ignition is switched off so if the pump has a direct 12v run to it, it will run with ignition off.

Once ignition is on the ecu leaves the pump control wire grounded for a few seconds then makes it an open circuit till you start the car.

That's how I understand it, may be completely wrong so you have to make up your own mind sifting through all the info online.

I didnt add a fuse in that drawing as I'm not smart to have put one in but will probably put one between the relay and pump to protect the wiring, again u have to make up your own mind on this one too ?

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Did add a fuse both on direct feed and feed to pump so 30 and 87

 

re ground, here is what i understand

relay needs power on 85 and 86 to energise and if one is missing then it will not energise and ciruit will be open

 

if i am using ecu positive to pin 86 then surely when ignition is off it shouldn’t matter whether i have an always on ground or ground from ecu but it did!

maybe someone with greater knowledge can clarify

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