Resolved 1G Fuel pump rewire, power with key on?

[allthrottle]

I know it's possible to have power to the pump with the key "ON", instead of just while cranking and running, but is there a reason why I don't see anyone doing this in any of the write ups?

Does the ECU/main relay have to be the one sending a signal to the pump, or would any turn on source do?

Whenever I'd have a pump related problem in previous cars, I usually ran a new power wire from a key on power source straight to the pump, and never had problems or noticed any driveability issues. They all seemed to start great, and my car has a difficult time staying started on the first try after sitting for 8+ hours.

Thanks

 

[toofast82]

1gs do not prime the pump with the key on, it runs while cranking.

The standard rewire procedure has worked very well for me on a few DSMs, don't try and reinvent the wheel. The point of the rewire is to eliminate small gauge wiring to give more consistent current and higher voltage through direct hookup to battery.

If the "key on" source is small gauge, this will eliminate any benefits to it.

 

[ilco187]

But you could hook it up the VFAQ way, just instead of using the input wire from the car to turn the pump on maybe you could substitute it with a 12v ignition type input, to turn on the fuel pump like the radio when the key is in acc, position.

just my opinion but

 

[allthrottle]

I did the rewire about a month ago and I'm satisfied with the result, I'm mainly wondering if there were a specific reason why I wouldn't be able to run a new "key on" signal wire to the new pump relay in place of the factory wire the originally went to the pump. Would there be any negative side effects to this?

That's what I'm thinking ilco. Unless the ECU is providing a variable signal to the pump, I can't see a problem. I think having the pump on before cranking could help cold starts in some cases.

 

[toofast82]

Sounds like you are trying to bandaid your starting issue. It's definitely not normal to have starting issues after sitting 8 hours. What is it doing exactly?

 

[allthrottle]

It usually stumbles for a couple of seconds first thing in the morning, or after a long shift at work. Every other day, it will start and stumble for a second and die, then fire up immediately and run smooth. It's not a huge issue, but it just got me wondering about the pump wiring. * I'm not having starting issues like others, where I have to keep cranking and cranking, than have it die a couple of times before it stays running. I only have to crank it for a second before it starts. It's just the cold start stumbles.

I'm not trying to use this as a band-aid for any problem, I'd rather fix it right the first time.

 

[pauleyman]

I did the rewire about a month ago and I'm satisfied with the result, I'm mainly wondering if there were a specific reason why I wouldn't be able to run a new "key on" signal wire to the new pump relay in place of the factory wire the originally went to the pump. Would there be any negative side effects to this?

I was looking for something and decided to answer this old post, there is definitely reason to not have fuel pump running in key on position. Do you want a broken fuel line to continue to pump gas onto a fire in the event of a crash?

 

[jed344]

I was looking for something and decided to answer this old post..there is definitely reason to not have fuel pump running in key on position. Do you want a broken fuel line to continue to pump gas onto a fire in the event of a crash?

Zero reason now days to have a fuel pump run all the time in key on. Set the ECU to do a post key on prime time to build pressure pre-crank if you want. Then ECU can also shut the pump off still too.

Same reason at a point and certain events when the battery is moved to rear of the car you need a kill switch on the rear of car. That way if you are not able to turn off power a track official can hit it and kill the cars power. All about safety.