Upgraded fuel pump wiring 10 gauge / awg

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Upgraded fuel pump wiring 10 gauge / awg

Postby Alikazam » Tue Apr 20, 2021 7:07 pm

So today I had to upgrade the fuel pump wiring to a 10 gauge wire. My car wouldn't start this morning due to no fuel. Efi main fuse, 15A, didn't look so good... (Plus fuel pressure gauge was not increasing when key switched on to prime and couldn't hear fuel pump) (edit: as in signature, not a stock ecu)

https://photos.app.goo.gl/kRBJuQRGue6e2WV28

Fuse box part was a little melted too but not bad. Swapped hazard fuse into it's place and stayed out of boost till I could get to the shop. Made it without issue and installed a new fuse. Ran the new 10 gauge wire down through harness hole and along passenger kick panel area, along passenger side panels by rear seat, into spare tire well, and finally to relay. Using a 25A fuse (walbro 450 pump can draw up to 22.5A according to website). Hopefully if anyone else needs to do the same this will help! Good luck! Feel free to ask any questions.

https://photos.app.goo.gl/o7txgEVGag5Mfcan8

https://photos.app.goo.gl/5Myj4zTguwSPBhS69

Also added the Amazon motortrend cargo liner with quick rough trimming until I can cut out a pearce of wood or something for a proper floor.

https://photos.app.goo.gl/oiCmcd4VAY6JVUx88
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Last edited by Alikazam on Tue Apr 20, 2021 8:11 pm, edited 2 times in total.
1990 Celica Alltrac - Emma
Gen 3 engine
KO Racing Street Brawler - Precision 5130 Turbo
KO Racing In Factory ECU Case - Link G4x ECU
327 AWHP @ 18psi - pump gas
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Alikazam
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Posts: 50
Joined: Sun Mar 27, 2016 5:10 pm

1990 Toyota Celica

Re: Upgraded fuel pump wiring 10 gauge / awg

Postby 93celicaconv » Tue Apr 20, 2021 7:50 pm

Just so you are aware, on a stock ST185, the fuel pump does not run when the key is turned to the ON position. The fuel pump only turns on with the ignition switch when the key is turned to the START position. There are a set of points in the AFM that, once the car starts and pulls air to open the AFM door a bit, the points switch state, which keeps the fuel pump running after the ignition switch is released on the ON position. You can call this a safety system so the fuel pump isn't left running after an accident or similar.
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Re: Upgraded fuel pump wiring 10 gauge / awg

Postby Alikazam » Tue Apr 20, 2021 8:08 pm

93celicaconv wrote:Just so you are aware, on a stock ST185, the fuel pump does not run when the key is turned to the ON position. The fuel pump only turns on with the ignition switch when the key is turned to the START position. There are a set of points in the AFM that, once the car starts and pulls air to open the AFM door a bit, the points switch state, which keeps the fuel pump running after the ignition switch is released on the ON position. You can call this a safety system so the fuel pump isn't left running after an accident or similar.


Just so you know, my car is running on a link g4x so it primes as it's programmed to. Also it's speed density with a gen 3 motor. Not stock. Other safety devices are installed and programmed in though. Fyi.
1990 Celica Alltrac - Emma
Gen 3 engine
KO Racing Street Brawler - Precision 5130 Turbo
KO Racing In Factory ECU Case - Link G4x ECU
327 AWHP @ 18psi - pump gas
Image
Alikazam
Club Member
 
Posts: 50
Joined: Sun Mar 27, 2016 5:10 pm

1990 Toyota Celica

Re: Upgraded fuel pump wiring 10 gauge / awg

Postby 93celicaconv » Tue Apr 20, 2021 8:15 pm

It's hard for anyone to provide assistance on vehicles that are not stock, because the non-stock modification options can be endless. However, if you have some modifications that others also have, then that subgroup can assist you. I just did not know what you had (I see you edited your post to indicate a modification now). Hopefully you will get your fueling issue resolved.
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Posts: 716
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Re: Upgraded fuel pump wiring 10 gauge / awg

Postby grip-addict » Tue Apr 20, 2021 8:34 pm

nice work, looks tidy.
I had to do something similar when I was troubleshooting fuel pressure issues with my walbro 255. Ended up sticking a multimeter on its connector while going on a drive and was seeing 10 volts on the fuel pump circuit while it was under load. Yes, the resistor is/was bypassed and the pump is running flat out all of the time.
Since my battery's in the trunk, I just ran my relay directly from the positive there and grounded out the ground to chassis. Stuck my relay behind the rear-most plastic trunk cover thing. That really helped (but didn't fully fix) my fueling issues.

I think Alikazam was just sharing a modification he did recently and what symptoms led to making the change. It's nice to see other members attempting to help out though. Our small community needs the positivity since there are so few of us left :)

BTW in case anyone is thinking about it, fuel pressure monitoring is a game changer. Fuel is safety, and you really are rolling the dice when making modifications and NOT getting fuel data back. Yeah, you know HOW the system is supposed to react in an ideal situation, but you don't know that's what it is actually doing. it's such a roll of the dice.

ok, off my soap box for now :D
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Re: Upgraded fuel pump wiring 10 gauge / awg

Postby Alikazam » Tue Apr 20, 2021 11:36 pm

93celicaconv wrote:It's hard for anyone to provide assistance on vehicles that are not stock, because the non-stock modification options can be endless. However, if you have some modifications that others also have, then that subgroup can assist you. I just did not know what you had (I see you edited your post to indicate a modification now). Hopefully you will get your fueling issue resolved.


It's all good. I wasn't asking for help. I was posting a performance modification. Also my signature says all of the above about my setup. Appreciate the attempt at help anyway.
1990 Celica Alltrac - Emma
Gen 3 engine
KO Racing Street Brawler - Precision 5130 Turbo
KO Racing In Factory ECU Case - Link G4x ECU
327 AWHP @ 18psi - pump gas
Image
Alikazam
Club Member
 
Posts: 50
Joined: Sun Mar 27, 2016 5:10 pm

1990 Toyota Celica

Re: Upgraded fuel pump wiring 10 gauge / awg

Postby Alikazam » Tue Apr 20, 2021 11:39 pm

grip-addict wrote:nice work, looks tidy.
I had to do something similar when I was troubleshooting fuel pressure issues with my walbro 255. Ended up sticking a multimeter on its connector while going on a drive and was seeing 10 volts on the fuel pump circuit while it was under load. Yes, the resistor is/was bypassed and the pump is running flat out all of the time.
Since my battery's in the trunk, I just ran my relay directly from the positive there and grounded out the ground to chassis. Stuck my relay behind the rear-most plastic trunk cover thing. That really helped (but didn't fully fix) my fueling issues.

I think Alikazam was just sharing a modification he did recently and what symptoms led to making the change. It's nice to see other members attempting to help out though. Our small community needs the positivity since there are so few of us left :)

BTW in case anyone is thinking about it, fuel pressure monitoring is a game changer. Fuel is safety, and you really are rolling the dice when making modifications and NOT getting fuel data back. Yeah, you know HOW the system is supposed to react in an ideal situation, but you don't know that's what it is actually doing. it's such a roll of the dice.

ok, off my soap box for now :D


Appreciate it and yes your assumptions are correct lol. Just trying to share a performance mod. Also, we monitor fuel pressure and oil pressure with some transducers that the ecu logs. Planning to install a canbus gauge eventually and have those both up on screen lol. It just takes $$$.
1990 Celica Alltrac - Emma
Gen 3 engine
KO Racing Street Brawler - Precision 5130 Turbo
KO Racing In Factory ECU Case - Link G4x ECU
327 AWHP @ 18psi - pump gas
Image
Alikazam
Club Member
 
Posts: 50
Joined: Sun Mar 27, 2016 5:10 pm

1990 Toyota Celica


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