So I just bought this liberty last week and its having two problems that even with my experience and basic knowledge I cannot identify to save my life. When in idle (park/neutral) it makes a revolving noise that sounds similar to the noise bad brakes would make but much less so. When I engage it into drive the noise either stops or very very faintly keeps going, when the engine rpm's increase so does the noise to a constant drone of screeches. Now the noise does not sound blood curdling to the point I'd think my car will explode but it is something I am concerned about. The weird thing is that it is not coming from the engine area and can only be identified from coming somewhere around the front third of the vehicle (almost center). All fluids and belts are good and as stated I know its in that area. All fluids are good and have been checked except the differentials. Also I sometimes get a strange burning smell which can not be identified and is not from the engine area either.
My car has 150000 miles.
My car has an automatic transmission.
This may very well be related to the catalytic converter in your car. As you know, the catalytic converter is responsible for converting toxic combustion gases into less harmful gases to be dispelled into the atmosphere via your car’s exhaust system. When this is clogged or your car is running very rich (too much fuel), this can cause the catalytic converter to overheat which will eventually result in poor fuel economy and poor running conditions. You may also notice a burning smell as you describe. If this is the case, you should also likely have a Check Engine Light on which would indicate that the vehicle needs to be serviced. If you need help having this scoped out, a certified professional from YourMechanic can come to your car’s location to pinpoint the cause of the noise and the smell so that this gets repaired properly.