Q: The RPM doesn't exceed 3 on the dash board when idling, and rpm doesn't exceed 2 when in motion. What is the cause?

Hi There, It sounds like you may have a problem with your transmission causing it to go into limp mode which will not allow the car to exceed a specific RPM or speed when driving. The transmission control module will purposely do this when there is an error detected in the transmission such as a faulty speed sensor or solenoid.

A clogged or failing catalytic converter can also cause the vehicle to run sluggish as you have described. As you may already know, the catalytic converter converts toxic exhaust gases into less harmful pollutants that are suitable to be expelled into the atmosphere. When this is clogged, this causes these gases to be backed up into the exhaust system not allowing the engine to breathe properly. When this happens, the engine is forced to work much harder to expel these gases. This often results in the engine bogging down, hesitating, shaking and causing very poor fuel economy. I would recommend having a professional from YourMechanic come to your location to diagnose and inspect your vehicle.