Truck surges, (tack comes down way low then jumps back up, then comes down way low then jumps back up), not all the time though. And only does it when in gear and stopped. Now (last 3 days) when I am slowing down to stop the car just dies/shuts off. Car starts up no problem but when I slow down again it dies.
My car has 19900 miles.
My car has an automatic transmission.
This sounds like you may have a faulty idle air control module. This is a component that monitors the flow of air into the engine at idle speeds. The purpose of this is to regulate the air being mixed with fuel prior to being injected into the motor. When this is faulty, it can cause the surging effect as you are describing. This could also possibly be a faulty mass air flow sensor which does something similar in that it regulates the amount of air being allowed into the intake system at regular speeds. I would recommend having your stalling issue diagnosed by a certified technician, like one from YourMechanic, who can come to your home to service your car as necessary.
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