Have a GSLSE running with a weber 45dcoe i am using the stock fuel pump and a regulator. When i crank the car over the fuel pressure goes up to 3-5 psi (which iw what the regulator puts out). Once it is started the fuel pressure goes to 0 and then a minute or two later it dies. I assume it is dying because of fuel starvation.

What have i missed? I know its probably going to be something simple like a pump rewire or a relay bypass. ANyone done this and know for sure? Thanks in advance.

 

I'm not an expert but your problem is probably that the stock fuel pump is designed for fuel injection.

I think you need a lower pressure fuel pump.

 

Check the fuel lines for kinks and check your fuel filter out.

A stock SE fuel pump should put out about 17 psi if I am not mistaken.

 

all lines are original from pump to regulator then i added new line for the carb and guage.

 

First, verify if there pump is running. Disconnect the fuel line between carb and regulator, turn on the ignition and see if any fuel will come out. Secondly, the stock F/I pump has too much fuel pressure. What kind of f/p regulator are you using? You mentioned wired incorrectly. Re-check it; maybe it was wires are reversed; therefore, its sucking the gas back.

mel

 

I really think its an elecrical issue anyone able to support or dispute this? Anyone else ever done this?

 

I never mentioned wired incorrectly. I havent touched the wiring on the fuel pump so i am sure it is wired correctly( it ran before i swapped it to carb). MY FPR is a rising rate FPR which has a boost input line for raising fuel psi for every boost psi i get. (this line is currently capped off since i wont be going turbo till dec/jan) I really suspect that since i have the wiring harness connections removed etc that it is not wanting to run correctly thats why i am leaning toward teh relay or some other form of electronic fuel pump cutoff.

 

knight1976,

I think that I may know what your problem is. The gsl-se has a switch in the air flow meter for the fuel pump so that the fuel pump will only run when the engine is actually running. I believe that the wiring is such that the pump runs in the ignition 'start' position but then relies on the AFM switch to run the pump when the key is 'on'. This is why you are getting the symptoms you are. You can check this by placing a jumper wire across the fuel pump check connector (rubber boot covered connector on the passenger side next to the tps check connector). This will cause the fuel pump to run when the key is in the on position. Hope this helps.

BTW, the SE pump should work fine with the proper regulator. I have seen others use it successfully in blow-thru turbo setups.

Kent

 

Kent, awesome info i will check into that a probably try that tonight.

Anyone else done this and have a permanant fix? Or even more input on the subject?

 

knight1976,

How about this? From the megasquirt website:

"You might want to consider a safety switch in the fuel pump circuit when installing an electric fuel pump. Holley has one (12-810, ~$20) that will ensure the fuel pump will not run unless the engine has oil pressure. It stops the pump from running if the motor stalls with the ignition on. Wiring the switch through the starter solenoid circuit energizes the pump on engine start-up. Once the engine has started, the switch continues to provide power to the pump as long as there is oil pressure to keep the switch turned on. "

I have not used one of these before, but I may need to use one as well because I am switching my SE to the megasquirt ECU and ditching the AFM. I will keep the AFM at first until I get some tuning done and figure out what I am going to do with my intake setup. Good luck.

Kent

 

Thanks that is very nice stuff!

Still hoping someone else on this site has dont this and has a 100% solution.

 

Keep in mind that your fuel pump was designed for a bypass regulator, not the one you are using. I don't know about the SE pump, but if you dead-head (if I'm remembering that term correctly) most EFI pumps, they overheat and die.

 

Yea this has a return/bleedoff valve so i should be good to go.

 

May I make a suggestion? You could get double duty out of a manual fuel/kill switch setup. Mount the switch in an inconspicuous area. It will serve both as a manual fuel pump switch (thus eliminating your starvation problem) and as an added level of security. If the car was ever hotwired, it won't run for very long- result: you keep the car.

 

i was thinking about that but i am afraid i would forget about it . Heard another idea i am going to try out and if it works i am going to post pics and a how to. And thank the person who gave me the solution of course.

 

mallory regulator?

 

Actually its a malpassi ( italian) regulator but gets marketed in the states under quite a few names.

 

Knight1976
check your pm.
chuck

 

Eddierotary actually had the 100% soulution to the issue. His car is running the same pump and carb as mine so he has already been through this headache. Basically the fuel pump relay just needs to be removed and the wire that supplies the fuel pump with power is wired to a switched 12v line(runs when key is in the on possition).

Thanks Eddie and thanks to everyone that helped me out.