Question about 1984 Chevrolet Camaro

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Vapor lock 84 camaro

I have an 84 z28 with a vortec carbureted motor. holley 600 cfm, had no place for a mechanical pump so i installed an electric inline and disconected the 'helper' pump in the tank added a fuel regulator insulated the hoses with insulation tape. but no matter what i do, if the weather is 70 degrees f. or higher, the car will lose power hesitate then die. then i must wait about thirty minutes for it to start back up. it already has a plate under the carb. i moved the hoses away from the heat the best i could. but when it stalls the constant stream turns into what looks like a spray from a bottle of windex or something. i cant seem to figure it out. also my battery all of a sudden started dying and cant figure that out either. the alternator and battery are both fine. im stumped please help!

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  • pantywaste33
    pantywaste33 Apr 18, 2009

    i just did a test. warmed it up to operating temp til it stalled. plugged up the helper pump and it ran for a few unplugged the helper pump and a min and half later it stalled again. i repeated again. as far as i know the 'helper' pump was installed on that model to prevent vapor lock. only problem is it stays on constantly even with the switch off. i am beginning to think i purchased a bad pump. it was the cheap thing from autozone, a

    E8012S. the return hose is plugged off, although i have also loosened the gas cap to be sure it is getting suffieceint flow so the pressure doesnt build up. i think the pump runs fine until it gets 'tired' at which point it drops pressure. thats why it runs better with 'helper' pump cuz its givin it that extra 'umph' . thats my thought. cuz it died today and the hoses were still cool. i dont understand how it could be vapor locked without heat.

  • pantywaste33
    pantywaste33 Apr 18, 2009

    oh and by the way the helper pump is in the tank. the inline pump is 'supposed' to be 5-9 psi it is mounted under the hood, and the helper pump plugs up under the car near the fuel tank.

  • gerry bissi May 11, 2010

    is the electric pump in the yank?

    How gph is pump capable of?

    What is fuel pressure?

    How does fule get through helper pump in tank taht you disconnected?

    I assume no return line?



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What you described sound like your vent tube on your tank is plugged so what happens is that your fuel is over pressure causing it to foam thus starving the carb and running your float bowl dry. I would start by looking at the tube that comes off the tank. as far as your battery is concerned check to see if you have a loose ground or a positive cable leading from the altenator and from the engine to the fram ground cable. if the altenator is charging but the ground is loose then the battery will not get replacement voltage. if there is a loose positive and ground cable loose from the altenator then once the voltage on the battery goes below 10 volts the car will stall because there is not enough voltage to energize the coil.

Posted on Apr 18, 2009


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