Mechanics

CHEVY ENGINE SUDDENLY LOSES POWER

1981 Chevrolet Malibu • V8 2WD Automatic • 100,000 miles

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?
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2CarPros-Archives
February 2, 2011.



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.

Tiny
2CarPros-Archives
Feb 2, 2011.
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.