I have a 2009 Chevy Impala, 3.5, V.6 and every time I get in the car for the past few weeks before even starting the car it makes a noise under the dashboard. Again this happens before I start the car and then the rumbling noise stops after I drive for a few minutes. Any ideas as to what could be causing this? Thank you
That is tough. Before the car starts the only thing really that heppens is when the key is in the "RUN" position one before the start position. When it is in this position the fuel pump primes the fuel system and you can hear the click of the relay and sometimes the pump. Could it be a metal on metal noise like if the fuel line guides/holders had lost their inserts and were shaking around? Or, could it be a gurgling noise like there is air in the fuel line?
Otherwise I cannot think of much that would make noise before starting.