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Q: Car will stall out at random while driving?

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I have a carbureted car with a 229 engine, 2 barrel, with one of the first CCC on it. Recently the car has started stalling out while driving it. It will run good at an idle, but will sometimes stall out at acceleration, or while just cruising down the road. The carb has been cleaned before and the vehicle just recently had a tune up (plugs/wires/distributor cap/fuel lines/etc). This is a very recent problem and seemed to happen after hitting a particularly bad bump in the road.

My car has 96000 miles.
My car has an automatic transmission.

Hey there. While it has been some time since I worked on one of these early CCC vehicles, the first place I would look is the carburetor itself.

If the vehicle idles fine but stalls or hesitates when hitting the gas pedal, the accelerator pump inside the carburetor may be faulty. When you hit the gas pedal, the engine needs an immediate increase in fuel. The accelerator pump provides that. It is a rubber diaphragm that with age, can harden and/or crack, which reduces it’s ability to respond to that immediate fuel requirement. Have a certified technician inspect the vehicle for a failed accelerator pump as it is the most likely cause.

One other possibility is the ignition control module, located in the distributor. Typically when they fail, they simply fail, providing no spark and the vehicle will not start. However, within the module are different circuits. One for cranking and one for running. An intermittent fault in the "running" circuit can cause a momentary loss of spark, particularly on heavy demand such as accelerating as the increased demand for power requires the module to alter ignition timing. While the module is a possible cause, in all likelihood, replacing the accelerator pump and/or rebuilding or replacing the entire carburetor with a rebuilt one will probably solve your issue.

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