IF I REPLACE THE CAPACITOR,WILL THIS STOP THE RATTLING NOISE?

You can try replacing capacitor or adding a booster for hard starting compressors, but it may be a bad compressor.

If you have extra used cartridge, try replacing the cartridge. If there's no noise, change your cartridge with a new one.

did they do an exhaust back pressure test to diagnose a plugged catalytic. if they did then replace it as there is no repair for this. the rattling you hear is the catalyst has come apart and is rattling inside the shell.

The start device is more than likely the problem. Run capacitors are rarely bad. If the start device rattles then it is bad.

The rattle is caused because the rpm is lower. When stopped in drive with one foot on the brake, press the throttle down slowly until the vibration stops and the noise goes away. Cause? Weak or bad motor mounts, loose bolts or parts.

Possibly a broken ceramic brick inside the catalytic converter.

It would not of fried the compressor ...your capacitor is bad...

The overload relay is the likely problem. See if it is burnt looking or if it rattles when you shake it. Or just replace it. It's not expensive. If that's not the problem then it's the compressor.

is it in a really cold area? Most refrigerators need to be in an area that is 55 degrees or above. If that isnt' the problem, the defrost timer may have a dead spot and be stuck in the defrost mode. The other thing that it could be is the start capacitor that is on the compressor. If you take it off and it rattles, chances are it needs to be replaced.

you need to replace the electronic control board $80.25