Before changing it. Remove it completely and check the condition of all the terminals. We were diagnosed as having a duff fuel pump and were raped to the tune of £500+ for a new pump to be fitted by a well known tuner

Picked the car up and it ran out of fuel due to the guage being ¼ of a tank out. Turned out to be nothing more serious than shitty contacts on the ecu plug

How pissed was I