Jump to content
SAU Community

Recommended Posts

ok so i put my walbro pump in today fitted strait up to my stock set up pretty much... plug and all!!! :blink:

then i attempted to do this 13.8 volts thing... bassicly

got a relay... had 4 terminals... 2 input and 2 out put...

2 inputs were 12v (dirtect battery feed...) and a ground...

with the out put... i cut the positive and put the 2 ends on the pos and neg.... and grounded the negaitve to the body...

i managed to get 12.5 or there abouts... did i do this wrong? any one who has ACTUALY done it got an answer for me??

it did drive like this but then it cut out n went all shit... had to take it back to stock wiring in the carpark of the local pub lol...

Link to comment
https://www.sau.com.au/forums/topic/322427-fuel-pump-dramas-need-help/
Share on other sites

well....you are checking voltage with the motor running right? 12vish is right for battery alone, alternator should show 13.5+

the wire you ran from the battery to the relay has 13.x at the relay end when the motor is running?

pins on the relay should be:

30 - wire to the battery (fuse near the battery)

85 - earth

86 - original fuel pump positive (signal)

87 - output to the fuel pump.

you should get the same voltage at pin 87 as the battery when the ignition is on.

have a look on the bottom of the relay, each of the pins will have a number stamped beside it. it should be the same number on all automotive relays, so hook up the wires to the pins Duncan said and it will work.

basically explained, pins 85 & 86 switch the relay which joins pin 30 to pin 87. so when the original setup tries to turn the pump on, you use the original positive feed to the pump and any ground to switch the relays coil, which connects the new 12v feed from the battery to the new fuel pump.

have a look on the bottom of the relay, each of the pins will have a number stamped beside it. it should be the same number on all automotive relays, so hook up the wires to the pins Duncan said and it will work.

basically explained, pins 85 & 86 switch the relay which joins pin 30 to pin 87. so when the original setup tries to turn the pump on, you use the original positive feed to the pump and any ground to switch the relays coil, which connects the new 12v feed from the battery to the new fuel pump.

ahhh thanx so so much!! I'll get onto it!! ;)

going off those pics, if you hold the relay the same way as in the pic this should work,

post-34711-1275003641_thumb.jpg

it also doesn't look like an automotive relay, but should still do the same job, just make sure you insulate the terminals so they don't short out on anything. if you want a proper automotive relay go to supercheap, they aren't expensive to buy.

its like that 3rd pic

the 12v on the left is from the ecu

the 12v on the right is from the battery

the ground goes to the chassis (make sure its a good contact, i.e. no paint in the way)

darren yes i have read that... and thats when i originally did but it did not work :) ill try the ways mentioned and see what happened... then im unplugging the pump and getting the volt reading from there correct?

going off those pics, if you hold the relay the same way as in the pic this should work,

post-34711-1275003641_thumb.jpg

it also doesn't look like an automotive relay, but should still do the same job, just make sure you insulate the terminals so they don't short out on anything. if you want a proper automotive relay go to supercheap, they aren't expensive to buy.

so i tryed this one and its getting power all the time now... do i stick with this and wire the battery lead into the acc.... or... have i stuffed it up once again...?

so ive played a little more... it only comes on with this set up when i turn the key... once its on pulling the fuse nere steering wheen doesnt stop it... and it doesnt no when to turn off?

Edited by chef_stagea

i went out and swapped my relay over.... got a proper automotive one... same problem.. turns on with ignition... runs at like 14.2 v then once you turn the key off... it turns the fuel pump off for a few seconds then keeps pumping and just flows threw the engin and back to the tank....and has to have the power cut from it momenteraly to stop it...

Edited by chef_stagea

on my relay...

pin 30 is my new 12v lead from battery...

pin 85 is earthed

pin 87 goes to the fuel pump (positive)

and pin 86 is the car end of the old positive lead...??

i did read somewhere about r33s having the negative wire on the fuel pump (untouched at this stage) grounded? i cant see this doing anything?

the reasoning behind grounding the old pumps negative is because there is a capacitor rigged up in the old pump setup, its there to help with power surges and general smoother running of the stock pump. because you are using the original pumps feed to switch a very low current drawing part (relay) it could be taking a while to dissipate the capacitors charge, hence the relay is staying pulled in. ground out that negative and see if that solves your problem.

ps. that last diagram you posted is what you said you have done anyway :)

Edited by QWK32

ahh OK I may have been wrong about pin 86 and 85.

Check if you keep positive voltage at the old positive feed more than 10 seconds after the ignition is turned on. Same check for the original earth - does it have continuity to earth more than 10 seconds after the pump is turned on.

If the positive drops out, old positive to 86 and 85 to earth

If the negative drops out, old positive to 86 and old negative to 85.

That should do the trick either way - as Josh said it might be earth triggered

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • OK, so regardless of whether you did Step 1 - Spill Step 2 - Trans pan removal Step 3 - TCM removal we are on to the clean and refill. First, have a good look at the oil pan. While you might see dirty oil and some carbony build up (I did), what you don't want to see is any metal particles on the magnets, or sparkles in the oil (thankfully not). Give it all a good clean, particularly the magnets, and put the new gasket on if you have one (or, just cross your fingers)
    • One other thing to mention from my car before we reassemble and refill. Per that earlier diagram,   There should be 2x B length (40mm) and 6x C length (54mm). So I had incorrectly removed one extra bolt, which I assume was 40mm, but even so I have 4x B and 5x C.  Either, the factory made an assembly error (very unlikely), or someone had been in there before me. I vote for the latter because the TCM part number doesn't match my build date, I suspect the TCM was changed under warranty. This indeed led to much unbolting, rebolting, checking, measuring and swearing under the car.... In the end I left out 1x B bolt and put in a 54mm M6 bolt I already had to make sure it was all correct
    • A couple of notes about the TCM. Firstly, it is integrated into the valve body. If you need to replace the TCM for any reason you are following the procedure above The seppos say these fail all the time. I haven't seen or heard of one on here or locally, but that doesn't mean it can't happen. Finally, Ecutek are now offering tuning for the 7 speed TCM. It is basically like ECU tuning in that you have to buy a license for the computer, and then known parameters can be reset. This is all very new and at the moment they are focussing on more aggressive gear holding in sports or sports+ mode, 2 gear launches for drag racing etc. It doesn't seem to affect shift speed like you can on some transmissions. Importantly for me, by having controllable shift points you can now raise the shift point as well as the ECU rev limit, together allowing it to rev a little higher when that is useful. In manual mode, my car shifts up automatically regardless of what I do which is good (because I don't have to worry about it) but bad (because I can't choose to rev a little higher when convenient).  TCMs can only be tuned from late 2016 onwards, and mine is apparently not one of those although the car build date was August 2016 (presumably a batch of ADM cars were done together, so this will probably be the situation for most ADM cars). No idea about JDM cars, and I'm looking into importing a later model valve body I can swap in. This is the top of my TCM A couple of numbers but no part number. Amayama can't find my specific car but it does say the following for Asia-RHD (interestingly, all out of stock....): So it looks like programable TCM are probably post September 2018 for "Asia RHD". When I read my part number out from Ecutek it was 31705-75X6D which did not match Amayama for my build date (Aug-2016)
    • OK, Step 3, if you need to remove the valve body, either to replace it, the TCM, or to do a more complete drain.  First, you need to disconnect the TCM input wires, they are about half way up the transmission on the drivers side. One plug and the wires are out of the way, but there is also a spring clip that stops the socket from sliding back into the transmission. On my car the spring clip was easy to get, but the socket was really stuck in the o-ring of the transmission housing and took some.....persuasion. You can see both the plug to remove (first) and the spring clip (second) in this pic Incidentally, right next to the plug, you can see where the casting has allowance for a dispstick/filler which Nissan decided not to provide. there is a cap held on with a 6mm head bolt that you can remove to overfill it (AMS recommend a 1.5l overfill). Final step before the big mess, remove the speed sensor that is clipped to the valve body at the rear of the box.  Then removal of the Valve Body. For this the USDM Q50 workshop manual has a critical diagram: There are a billion bolts visible. Almost all of them do not need to be removed, just the 14 shown on the diagram. Even so, I both removed one extra, and didn't check which length bolt came from which location (more on that later....). Again it is worth undoing the 4 corners first, but leaving them a couple of turns in to hold the unit up....gravity is not your friend here and trans oil will be going everywhere. Once the corners are loose but still in remove all the other 10 bolts, then hold the valve body up with 1 hand while removing the final 4. Then, everything just comes free easily, or like in my case you start swearing because that plug is stuck in the casing. Done, the valve body and TCM are out
    • OK, so if you are either going for the bigger fluid change or are changing the valve body which includes the Transmission Control Module (TCM), first you should have both a new gasket 31397-1XJ0A and a torque wrench that can work down to 8Nm (very low, probably a 1/4 drive one). You can probably get by without either, but I really didn't want to pull it all apart together due to a leak. First, you now need that big oil pan. The transmission pan is 450 long x 350 wide, and it will probably leak on all sides, so get ready for a mess. There are 24x 6mm headed bolts holding the pan on. I undid the 2 rear corners, then screwed those bolts back in a couple of turns to let the pan go low at that end, then removed all the middle bolts on each side. Then, undo the front corner bolts slowly while holding the pan up, and 80% of the fluid will head out the rear. From there, remove the remaining bolts and the pan is off. You can see it is still dripping oil absolutely everywhere...it dripped all night.... I got another couple of litres when I removed the pan, and then another few when I removed the valve body - all up another 4l on top of the 3 already dropped in step 1.
×
×
  • Create New...