1981 Chevy Malibu engine suddenly loses power

1981 CHEVROLET MALIBU
100,000 MILES • V8 • 2WD • AUTOMATIC
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1981 Chevy Malibu with a 305 cubic inch engine with a two-barrel Carburetor. While driving at approximately 40-55 MPH engine suddenly loses power (no sounds/as if stalled). As the speed falls below 40, the engine kicks back on. This repeats if trying to accelerate again. I have replaced the fuel pump, rebuilt the carburetor, and changed the distributor and coil. While "power-braking" the engine, the fuel enters the carburetor for about one minute then the engine dies. It acts as if it is starving for fuel. Could a hose collapse from the fuel tank cause this condition? If not, what could?
Feb 2, 2011 at 7:12 PM
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Check for fuel in the carburetor when the engine dies after power braking to isolate the problem to the fuel system. Some possible causes include: 1. Cracked fuel hoses at the tank of pump, 2. Partially plugged fuel pick-up filter in the gas tank, 3. Incorrect gas tank cap causing a vacuum in tank, 4. Alternator diode failure allowing AC voltage to ignition coil. (Try test-driving with the alternator disconnected.), 5. Faulty ignition module in Distributor.
Feb 2, 2011 at 7:13 PM
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DAVE'S BIG BACKYARD!
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the one thing i need to know is if you pump the gas pedal will it take off again? if so then it sounds like your carb,sometimes a rebuild dont work.
Feb 3, 2011 at 1:52 AM
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