2003 dodge caravan 3.3L will only run for 3seconds and shuts off.
Have replaced computer and still dose the same thing!!

Any codes in the computer?

. Check all under hood and under dash fuses with a test light or multimeter.

. Check for codes.

. Check for fuel. Ensure there's more than just a token amount of gas in the tank. Can you hear the fuel pump run, when the ignition switch is turned to ON? Replace the fuel filter, if it hasn't been changed in 25,000 miles. Check the fuel pressure, if there are any doubts about it.

. Check for spark. If there's no spark or it's weak, consider replacing the Crankshaft Position Sensor and the Camshaft Position Sensor. Ensure that you are only using the same Champion spark plugs that originally came in the vehicle.