Why does the abnormal noise disappear when the VVT plug is unplugged in the Regal?
2 Answers
The specific reasons and solutions for the abnormal noise disappearing when the VVT plug is unplugged in the Regal are as follows: Specific reasons for the abnormal noise disappearing when the VVT plug is unplugged in the Regal: The abnormal noise disappears when the VVT plug is unplugged in the Regal simply because the load on the timing belt is reduced at this time, so the noise heard also decreases. However, the timing belt is still in a loose state. If this condition persists for a long time, the belt may slip off, leading to engine damage. Solutions for the abnormal noise disappearing when the VVT plug is unplugged in the Regal: This is a defect in the timing system. The abnormal noise from the engine is caused by the loose timing belt. The tensioner spring of the timing belt loses its elasticity and cannot hold the timing belt properly. Therefore, simply tightening the timing belt or replacing it can solve the problem.
I've driven quite a few Buick Regals, and the rattling noise disappears after unplugging the VVT connector, usually because there's an issue with the VVT (Variable Valve Timing) system, such as a stuck solenoid valve or a jammed actuator lock pin. When the connector is plugged in, the engine control unit sends signals to activate the VVT, but worn components or insufficient oil pressure can cause it to move unevenly, resulting in squeaking or grinding noises. After unplugging, the VVT system deactivates, the actuator locks in the default position, and the noise naturally stops. However, this is only a temporary fix—don’t drive like this long-term, as without VVT optimization, the engine will consume more fuel and lose performance. I recommend checking the oil quality promptly; dirty or contaminated oil can clog the VVT oil passages. Replacing the solenoid valve usually solves the problem. Get a full diagnosis done soon to avoid bigger trouble.