If a truck will start but wont stay running what might the problem be?
Is it a truck with a Sentinel (chipped) key? Your key might have lost its programming. If it starts fine and then only runs for a few seconds, the same amount each time, this is most likely the cause.
Could use a tune up.
blown head gasket possibly, does it overheat quickly
Clogged fuel filter among many things
Could be a fuel injection issue if it isn't overheating. Do you hear a squealing noise when it's running? Or a humming?
Of its carberated it's the jets if fuel injected they are clogged