I then turn key on and you hear pump in gas tank pump up ,but you donot hear external pump ,you let sit an hour and starts and runs fine and you hear external pump running while engine is running ,replaced both fuel pumps three years ago and fuel pump relay feels hot ? I am thinking external pump is bad.
My car has 300000 miles.
My car has an automatic transmission.
The fuel pump in the fuel tank is designed to have low pressure and high volume to feed the front fuel pump the right amount fuel. The front fuel pump supplies the engine with high pressure to the engine.
When you do not hear the pump run then the fuel pump is bad and should be replaced along with the relay. You should not have to replace the in tank pump if it is running. I'd suggest replacing the fuel filter as well.
I'd suggest getting this inspected by a qualified technician, such as one from YourMechanic, to diagnose your stalling issue and make the necessary repairs.
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