Resolved 2G Need help re-wiring walbro 255

[2GEEZEY]

I was reading the vfaq, but the pictures are to small and not really detailed, its hard to follow what the guy is doing.

I was wondering if anyone has better pics or a link that could help me out. My battery is relocated to the trunk so i dont have that much wiring to do, just a little confused about it.

any help would be greatly appreciated, thanks

 

[gofer]

You owe me for this drawing...

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[DSM_PWR]

^^ not bad

 

[2GEEZEY]

wow!!! i cant thank you enough!! thats awesome!

so for all those wires, i use 10 gauge wire?

 

[mike96]

no, just for the wire going from the battery to the relay and relay to the fuel pump connector... unless you really want to go overboard like i did, i replaced the ground wire with 10 gage and the wiring inside the tank as well...

 

[steve]

You owe me for this drawing...

A couple of suggestions.

By convention the 30 pin is the power input for the contacts and 87 or 87A the output. In 99% of the cases it won't matter operationally. There are relays with internal diodes for quenching the back EMF when you turn off the coil. You have shown the correct polarity for the coils that will work with both protected and non-protected relays. (86 more positive than 85)

Don't tap into the fuel pump ground for the relay's ground. It increases the chance of a failure and it's easy to run a self tapping screw into the chassis or use and existing bolt. The relay only uses a few milliamps in the coil when activated so just about any ground point will do.

People often use cheap ATO style fuse holders (like you would find at Radio Shack) for the power from the battery and they have a nasty habit of melting because of high resistance in the connector or internal crimps. I've seen this mostly with Denso pumps since they draw more current than the Walbro pumps.
Find a Car Audio style fuse rated at > 20 amps to use here, it's less likely to melt.

 

[2GEEZEY]

okay then i just take the wire from the fuel pump harness and conect it to the relay?

 

[black_gst]

A couple of suggestions.

By convention the 30 pin is the power input for the contacts and 87 or 87A the output. In 99% of the cases it won't matter operationally. There are relays with internal diodes for quenching the back EMF when you turn off the coil. You have shown the correct polarity for the coils that will work with both protected and non-protected relays. (86 more positive than 85)

Don't tap into the fuel pump ground for the relay's ground. It increases the chance of a failure and it's easy to run a self tapping screw into the chassis or use and existing bolt. The relay only uses a milliamps in the coil when activated so just about any ground point will do.

People often use cheap ATO style fuse holders (like you would find at Radio Shack) for the power from the battery and they have a nasty habit of melting because of high resistance in the connector or internal crimps. I've seen this mostly with Denso pumps since they draw more current than the Walbro pumps.

so do not use a common ground for the relay and FP right?

 

[steve]

so do not use a common ground for the relay and FP right?

The only problem with the way shown is that is your weakening the ground wire by tapping into it. You could run the relay ground to the same screw as the pump ground if you wanted to.

 

[2GEEZEY]

i dont have to use 10 gauge wire for the grounds?

 

[steve]

It's not a bad idea. I don't know how long the ground wire is on a 2G, it's pretty short on a 1G AWD and it's the combination of wire gauge and length that controls the voltage drop.

The power line is a big issue since it's small and winds it's way around the car before getting to the pump but the ground could be pretty short and the smaller gauge wire enough to do the job.

Just remember when dealing with power wire gauges it's both the source and return (ground) lengths that get counted.

 

[2GEEZEY]

okay so i finished re wiring it, when it start it, its not loud, like how u can here the whine before it starts, it doesnt do that.

like it doesnt do this: YouTube - ‪DSM Exhaust‬‎

 

[gofer]

Steve I must be half retarded I guess because I can't interpret what your saying is wrong with the wiring diagram I posted up top. Your saying that it should be like the diagram below then? This is fairly important since that diagram above is drawn IAW the VFAQ fuel pump rewire install instructions. I've been running it like the above diagram for almost 3 years with no hiccups.

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[Aproductions]

so this is how it should look????

 

[gofer]

HAHA. Your like me Alex, I can't read something and understand what the hells going on I've got to see a picture of it or else I'm lost.

 

[2GEEZEY]

I did it how you orignally showed me gofer, which is the same way on vfaq, started it up and runs fine. Although can you answer my question? about the loud " whining noise" it makes before the car actually starts? in the video above, that guy has a rewired 190

 

[Aproductions]

HAHA. Your like me Alex, I can't read something and understand what the hells going on I've got to see a picture of it or else I'm lost.

yeah it sucks sometimes but I'm a visual learner.


we posted the same picture at the same exact time haha

 

[gofer]

Great minds think alike!

Glad to hear its working, I was about to say my cars magical then if the first post I made was wrong. I understand what Steves saying by "weaking" the ground but at the same time its still better than stock even though its tapped since the ground on the stock harness is many feet away. Watch the very first part of that youtube video... 2.4L Spyder ... which means its not a 4g63 DSM. I'm sure they are wired differently and I know for a fact that my fuel pump has never actuated on until I've actually tried turning the car over.

 

[Aproductions]

what is the difference in your first picture gofer and my picture?

 

[2GEEZEY]

Prime thats the word. Mine doesnt prime before i start it. Yeah its a 2.4 but isnt a 190 pump smaller? i was just surprised mine doesnt do that, i was hoping it would.

 

[Aproductions]

did we ever get this picture thing resolved?

 

[steve]

By weakening I mean that by tapping or soldering to the existing ground wire you physically weaken it making it more likely to fail.

The fuel pump doesn't prime until you start cranking the starter. It's not intended to do it when you turn the key on.

Here's what I was talking about regarding the terminals. It doesn't make a bit of difference in function it's just convention. I just moved the terminal labels.

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[Aproductions]

so you used my drawing for the grounding part?

like thats better than cutting into the other wire and then grounding it?

 

[steve]

I could have used either picture. Gofer's makes it clear you don't touch the existing ground for the pump but I grabbed yours.

 

[Aproductions]

thanks, so I'll use the last picture you posted correct>?