fuel pump backup switch delete? oil pressure
#1
fuel pump backup switch delete? oil pressure
the fuel pump backup switch on top of the oil filter,,can it be deleted,if so,how, just disconnect it and leave the circuit open? or connect both wires together closing the circuit to bypass, please just answer if you actually KNOW FOR SURE , if i wanted to guess,id try it and see, i dont want that, im redoing my harness neatly,wanna deal with it now once and for all,and i want my car to work,its a tpi transplant.
#2
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Car: GTA
Engine: 350 TPI
Transmission: 700R4
Axle/Gears: Aussie 9-bolt/3.27 posi
Re: fuel pump backup switch delete? oil pressure
Gotta ask.....WHY would you want to? It helps to save your engine if the pressure drops in the event you don't see the drop & turn the ignition off yourself. My .....I wouldn't bypass it. Just clean up the wiring.
#3
Re: fuel pump backup switch delete? oil pressure
i have a good reason
i know what im doing, just wanna know what i asked about, the hole in the block has been plugged,the then welded,the sshaved, to a point you dont even see the hole anymore, plus i already dropped the motor in the car,cant drill it with motor in car, i could mount it on top with the other one,but,,,,,,anyway, i want to delete it.
i know what im doing, just wanna know what i asked about, the hole in the block has been plugged,the then welded,the sshaved, to a point you dont even see the hole anymore, plus i already dropped the motor in the car,cant drill it with motor in car, i could mount it on top with the other one,but,,,,,,anyway, i want to delete it.
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Re: fuel pump backup switch delete? oil pressure
It's not better than nothing, it is nothing. As in 0% guaranteed protection. The OPSU will not shut down the engine on low oil pressure as long as the fuel pump relay works, and is not intended to.
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Car: GTA
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Re: fuel pump backup switch delete? oil pressure
Apparently you did not understand "I didn't say it was 100% guaranteed protection, but it is better than nothing". Please forgive me for assuming that you being a Moderator & able to use a computer indicated you had some intelligence & understanding of the English language. I see now that I was wrong & will now Unsubscribe so that I do not torture myself by trying to explain simple English AGAIN.
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Car: 1984 Z28 Hardtop
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Re: fuel pump backup switch delete? oil pressure
It does have a purpose, but that purpose has nothing to do with saving the engine from low oil pressure.
#12
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Car: 82 Z28
Engine: 383 SP EFI/ 4150 TB
Transmission: T400
Axle/Gears: QP 9" 3.73
Re: fuel pump backup switch delete? oil pressure
You are just perpetuating a myth popular with newby owners.
Only have to look at the circuit diagram which obviously you haven't or don't understand
to see that taking the OP switch out of operation ( from low oil pressure ) has no effect on pump
because the OP switch is wired in parallel with the pump relay which is closed and also sending
power to the pump anytime engine is running
Last edited by vetteoz; 03-20-2012 at 04:52 PM.
#13
Re: fuel pump backup switch delete? oil pressure
what is this some kind of ****in kindergarden? wtf?! i got my answer, blackenedbird just said what he thought,like 98% of the bullshit on this site,he happened to be wrong, why be a smart *** again, jesus christ ,this is a site to find info,not to bitch at each other like a bunch of retards, as soon as someone know better than the other one, he has to make the other one look stupid? maybe the guy that is stupid in diagrams on a car,, can be a heart surgeon looking for advice for his camaro.cut the crap for **** sake. thanks everyone for your 2 cents, i finally got all the stupid plumbing i needed to keep the damn thing dangling in the engine bay.
#14
Re: fuel pump backup switch delete? oil pressure
i actually rewired the whole freekin thing from scratch, i know the damn diagrams, i just dont remember 100% by heart, turn to this site for info, does that mean im stupid too?
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Car: 82 Z28
Engine: 383 SP EFI/ 4150 TB
Transmission: T400
Axle/Gears: QP 9" 3.73
Re: fuel pump backup switch delete? oil pressure
So if you followed blackenedbird 's advice and your engine blew up while you were waiting for the switch to
"save your engine if the pressure drops "
you would be happy because his feelings weren't hurt because nobody told him he was wrong ?
He doesn't understand how it works, BELIEVES he is right and is arguing the point
At no point does he explain WHY he is saying what he does
Maybe the diagram will let him see things better?
"save your engine if the pressure drops "
you would be happy because his feelings weren't hurt because nobody told him he was wrong ?
He doesn't understand how it works, BELIEVES he is right and is arguing the point
At no point does he explain WHY he is saying what he does
Maybe the diagram will let him see things better?
Last edited by vetteoz; 03-21-2012 at 12:33 AM.
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Car: 1989 Formula
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Re: fuel pump backup switch delete? oil pressure
First off, sorry for dragging up an old thread. But, what is the purpose of the OP switch? Reason I ask is I'm having a problem with my car that I've been researching all evening. Car will not crank until oil pressure has built up to about 5-7 psi. Once running, it runs fine. Can spray a bit of starting fluid in, and it'll crank immediately, and then of course the oil pressure is up and will run great. Been extremely consistent that every time oil pressure builds, it will start.
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Car: 82 Z28
Engine: 383 SP EFI/ 4150 TB
Transmission: T400
Axle/Gears: QP 9" 3.73
Re: fuel pump backup switch delete? oil pressure
Check the circuit diagram I posted above.
OP switch is a backup switch for the fuel pump wired in parallel to the pump relay;
if the relay should fail ( or computer fail to operate relay ) you will still get the fuel pump to run ( and have fuel pressure )
from the OP switch once the oil pressure is over 4psi ( while cranking )
Do you mean engine will CRANK over but not FIRE up until you have oil pressure
You can not get oil pressure if the engine is not cranking over ( cranking = rotating /turning on the starter )
OP switch is a backup switch for the fuel pump wired in parallel to the pump relay;
if the relay should fail ( or computer fail to operate relay ) you will still get the fuel pump to run ( and have fuel pressure )
from the OP switch once the oil pressure is over 4psi ( while cranking )
Do you mean engine will CRANK over but not FIRE up until you have oil pressure
You can not get oil pressure if the engine is not cranking over ( cranking = rotating /turning on the starter )
Last edited by vetteoz; 05-26-2012 at 11:26 PM.
#19
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Re: fuel pump backup switch delete? oil pressure
Sorry, yes that's exactly what I meant. I came to the conclusion that the relay may be the issue a little while ago also. Getting ready to find out for sure in a few minutes. Just kept on thinking it was a wiring issue since it just started when I swapped in the 5 speed. I'll update when I find out for sure, thanks for the help!
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Car: 82 Z28
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Re: fuel pump backup switch delete? oil pressure
but also be aware could be a problem with the wiring/ connections that controls the relay from the ECM
Relay should operate for 2 sec when key 1st turned on
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Re: fuel pump backup switch delete? oil pressure
Yeah I did some testing last night, it's not priming the pump when I turn the key, but the pump will run if I connect a wire directly between the two wires on the OP switch. I switched the relay with the cooling fan relay and it didn't do anything. Going to actually test the relay today (apply power and ground to the switched side and measure ohms across the big side), and track down that inline fuse and check it.
On a somewhat related note, does anyone know what the two extra wires that ran to the automatic shifter are for? There's the two large ones for the neutral safety switch (I have them bypassed for now until I hook up the clutch safety switch), two for the reverse lights, and two more that I haven't been able to track down on any wiring diagrams so far.
On a somewhat related note, does anyone know what the two extra wires that ran to the automatic shifter are for? There's the two large ones for the neutral safety switch (I have them bypassed for now until I hook up the clutch safety switch), two for the reverse lights, and two more that I haven't been able to track down on any wiring diagrams so far.
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