Swap starts and has oil pressure, will not stay running though Options

[6G94celica]

So heres the scoop. i got my swap completed and ran good. then i put the walbro fuel pump in and we got a problem. it wont stay running. it will first start up fine, run for about 15 to 20 seconds and die. i can hear the fuel pump running when i start the car and a second after it dies but it does not run and pressurize while it is in the run position. im thinking fuel pressure regulator for why it wont stay running because it wont hold pressure. another reason i think this is because after it dies it wont start again for 10 minutes or so. but im wondering why the pump does not run while the key is in the run position. i checked the plug and there is one pin that has 12 voltts on run but it goes to that tiny silver cylinder on the bracket and im not sure what that does. if ANYONE has any info please let me know im dying to drive my car. thanks so much

[LewFX]

or might be a fuel pump relay like what my cars problem is