Q: Car shuddering

When the vehicle stability assistance (VSA) control module detects wheel spin, it sends a request to the modulator unit to apply brake pressure to slow the spinning wheel. At the same time, it sends a signal to the traction control unit to reduce engine power. By doing this, the VSA system improves vehicle stability. If the VSA control module detects a problem in the system, it will illuminate the VSA light. On the other hand, the Check Engine Light comes on when the powertrain control module (PCM) has detected a problem in one of the powertrain systems. The symptoms you are experiencing (shuddering and poor acceleration) have dozens or potential causes. Retrieving the corresponding diagnostic trouble codes with dedicated equipment will help analyze both problems. I suggest having a professional, such as one from YourMechanic, service your vehicle to determine what repairs are needed to clear these lights.