Fuel pump wiring.

[celupra]

If my fuel pump was wired directly to the batery with a on off switch, no relay. Would that cause the car to miss up top end for some reason?.
Like does the ecu need to controll the fuel pump

[J0RD0]

maybe and yes, hope this info has helped

[brett_celicacoupe]

as long as you meet the voltage and current requirements of the pump then the engine will be fine.

check the current rating of the switch and pump.

use appropriate gauge wire..

the ecu doesnt have to control the pump.... its typically wired through the ecu to only run it while the engine is running/starting. some ecus control a high/low fuel pump speed circuit also

[celupra]

Ok, How do i work out the requirements?

[brett_celicacoupe]

the switch you buy should have a label..

if the fuel pump is stock then i guess you would be safe with a 15A switch.

there should be wire size/current capability tables on the net, have a search on google

[celupra]

All right i'll do that now. Thanks

[Hen]

For safety's sake put a circuit opening relay or tachometric relay in to control the pump. Both have been covered here. And both make sure the fuel pump stops if the engine stops.

Hen

[GA61XX]

Q:- was the car EFI..??? RA60 maybe not..

Q:- What size is the fuel line..???

Q:- did you change the fuel line..??? Use RA65 fuel line & tank...

You should have a 3/8" or 9mm or larger fuel line...

[Glenno52]

Do not wire directly to battery via switch! Do what Hen says.
Think about it....Crash...Engine might stop but Fuel pump will keep running and if any fuel line is broken ....fuel everywhere...not worth the risk!

[trd3sg]

its actually illegal to have it wired hot

you need a relay which is switched by the same ignition source as your alternator to stop it from running in the event of an accident

had a mate lose 60% of his mental capacity because of this issue - had a crash, engine switched off, fuel pump kept going, bang - knocked out in a burning car with no one to save him until fire brigade got there - was in a coma for 6 days

[celupra]

Its not staying like this, its just to get the car running at the moment, its a track car, I am going to wire it right, i was just asking would that effect the performance of the pump

[celupra]

Oh is that 3/8s od or id?

[EldarO]

usually lines are quoted ID.

[celupra]

Just making sure.
Im pretty much narrowing it down to the fuel pump not having enough guts.