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Q: Car turns over but won't start

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Was driving fine then next morning it wouldn't start. We have now tested gas supply to the carburetor and sparks to the plugs and both of them are good. When cranking and gas pedal pressed to the floor we can hear what sounds like one fire during the cycle of the engine. We are wondering if we probably need to do a carburetor rebuild?

My car has 50000 miles.
My car has an automatic transmission.

Hi there. I would recommend checking for vacuum leaks to determine if this is possibly leaning out the fuel charge going into the motor. When too much vacuum is present this will cause a lean air/fuel charge to be injected into the motor which is sometimes not enough fuel to cause the motor to fire. If no vacuum leaks are present, then I would next check to be sure the carburetor is pumping enough fuel into the intake manifold. Depending on the model of carburetor, this should be easy to see when taking the air cleaner off and looking down the barrels of the carburetor. With the air cleaner off, have someone press the gas pedal a couple of times. You should be able to see a nozzle squirting fuel down the barrel. If you do not see this, you may have a bad accelerator pump. It may not be a bad idea to rebuild the carburetor if it has been a long time or if the car has been sitting for a while. Gaskets and things like an accelerator pump can often go bad when sitting for long periods of time. If you would like help having this checked, a qualified professional from YourMechanic, can come to your home or office to inspect the starting issue.

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