Question about 1991 Chevrolet Corvette

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How long should the fuel pump relay stay energized before going off on a 1991 chevy corvett. when i first cut my switch on it only energizes for about 2 secounds then drops out. the car is hard to crank but runs fine after. i do not think the relay is staying on long enought to start the car properly any suggestions

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It should only stay on for a few seconds,you have an underlying could be either your fuel pressure regulator or the check valve in the pump itself might be letting the fuel drain back into the tank,im guessing the car only does it after it has been sitting for a little while and after the initial hard start it will keep starting normally,the easiest way to test it is to put a fuel pressure tester on it and start the vehicle or just pressurize the lines by turning the key on and see if the pressure drops,if it does, pressurize the lines again and crimp of the line from the pump wherever it is rubber with a pair of vise grips and see if it drop then..if it doesnt it will need a pump if it does it will need a fuel pressure regulator,im guessing this car has a L98 5.7 ltr TPI engine in it

Posted on Oct 12, 2010


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