Replaced crank relay, car won’t stay on

Hi, this is Bo, an auto expert on RepairPal's Car Genius team! When your car cranks but dies immediately after replacing the crank relay, it sounds like there might be an issue with fuel delivery or the security system. If the fuel pump and relays are working, check the fuel pressure to ensure it’s within the proper range. Sometimes, a weak fuel pump or clogged filter can cause this issue. Additionally, make sure the immobilizer or anti-theft system isn’t cutting the engine off—it can sometimes reset or malfunction after such repairs. Another thing to check is the crankshaft position sensor; if it’s not giving a good signal, the engine might cut out. Don’t worry too much; you’re on the right track, and a bit more troubleshooting should get you up and running! If you have any other questions, please call us at 877-913-1554! We'll gladly find you a certified RepairPal shop in your area!