Q: engine revs up and down when in park and it dies when puts in drive

Hello, thank you for writing in. There a large number of components that can cause these issues. If you have not scanned the vehicle for diagnostic troubleshooting codes, you will want to do that first. Even without a check engine light on, there may be an issue that the computer systems have already detected. Without any codes, you will need to test various systems in a process of elimination until you find the issue. At that point, you want to focus on your idle air control valve first. Verify you are getting properly air, fuel, and spark. Check into the transmission and torque converter after that. For more help with testing, contact our service department to schedule an appointment.