bad fuel pump symptoms?

[quagmires_sho]

i think maybe my fuel pump is going out, because car starts idles real good for about 3 seconds and then it feels like fuel gets cut to most of my cylinders and thats when the misfires start. it also SOUNDS like its going out, when car ran semi-normal it was already real loud so the car running poorly could've been enough to hold the pump on life support but the second i fixed the vacuum leak, it maybe was just too much stress and it shat the bed? idk what to think atp im definitely out of my element with this yamaha engine nonsense. it was getting most of the spark and ab 2/3 of the air itd usually get. i still need an ICM, so maybe the sudden change in air amount didnt give the computer time to relearn? this problem arose right around when the secondaries would stop opening n now its nearly inoperable. any help appreciated. tl;dr-my car runs bad (like 1-2 cylinders) and repair i made to vacuum system caused stress that the fuel pumps condition was NOT prepared to endure so now i think i need pump AND ICM

 

[zoomlater]

You can check the fuel pressure at the Schrader valve to see what pressure your fuel pump is putting out. Remove the cap on the valve, its in the middle of the intake, turn the key to on on position, but don't start it. Depress the valve and see if fuel comes out, you may want to put a rag over it as it can shoot straight up. If you have access to a fuel pressure gauge, you can screw that on and then check it that way. Fuel pressure is suppose to be around 30 to 35 psi

 

[luigisho]

I don't understand this diagnosis.
This car is F'd up. Every system has to be looked at and see if it is operating within operational parameters. AIR, FUEL, SPARK, TIMING, SENSOR OPERATION, DC POWER
You can jump from one system to another but without a gameplan you will likely run in circles until you give up.

First fuel pressure test... need analysis....

Bought a new FP gauge at Advance Auto and ran the test tonight. Key on pressure: 0 psi. After about 6 primes I got it up to 30 psi but it immediately dropped back to 0. Idle pressure: 30 psi. A stiff rev to the throttle brought it up to about 33 or so for about 3 seconds then back...

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