I have a 98 civic with a Walbro fuel pump which humms pretty loud which I previously found out was normal. Car starts fine but when I put it in first gear, I can hear the fuel pump knocking and if I proceed to drive, the engine just dies. Alternator and battery have been checked and are working fine. Somebody told me it might be the Main Fuel Pump Relay. Has anyone heard of this problem before? Any help would be great.