As the title says, my newly purchased used Tregg(60k miles V8 ) is having a hard time starting. It turns over but it takes like 15 seconds for the engine actually start running. If I turn the key back and try again, it starts fine. Only misfire codes. The truck is at a reputable local independent shop. Reading other threads I suspected it was crankshaft position sensor, but the engine runs fine once started up. It makes no difference if the tank is empty or full. Could it be the fuel pump?