Since we did not install the parts on your vehicle, we cannot assist you in diagnosing your mechanical issues at no charge. The service that you have paid us for is calibrating (tuning) your vehicle, not diagnosing and fixing mechanical problems. If we get into tuning your vehicle and there is a mechanical issue, we can assist in diagnosing it but charge a fee of $75/hr for said service. Since many times we run into situations where we believe the vehicle has a mechanical issue but the customer believes it is calibration-related, we will refund any diagnostic fees if we find the issue to be a calibration-related problem. If you purchased your parts through us, we will assist as much as possible in diagnosing any mechanical issue with the parts. As much as we wish we could help fix every issue on every vehicle, it is often inefficient for us to do so remotely not to mention it is outside of the scope of work we were originally paid to do.