The problem is on the front brakes or rear, this happen after I drive the car in heavy rain

Hello,

This is a common problem on the VW polo and Golf after heavy rain or vehicle been through a car wash and vehicle parked up without getting brakes warmed up and dried out the rear brakes bind up inside the drum. place the vehicle in gear, and chock/block in front and behind the front wheels to prevent vehicle from rolling, remove rear wheels from vehicle, release the handbrake and tap around the drum several times and you will feel it release and start to turn like it should. do this to both sides if they are both jammed on and drive vehicle once back together to get warmed up and remove residue.

https://www.2carpros.com/articles/how-to-replace-rear-brake-shoes-and-drums

I have added the above link just to give you an idea of the parts involved.

I have added a diagram of the rear drum brake setup in case you want to remove the drum and clean them up.

Hope this helps with your repair. Please keep us updated on your repair outcome and do not hesitate to contact us again for further information or assistance.

Check out the diagrams (Below). Please let us know if you need anything else to get the problem fixed. Thanks for using 2CarPros. Dave H

Here is a guide that will help with replacing the rear brakes as it sounds like this needs to be replaced:

https://www.2carpros.com/articles/how-to-replace-rear-brake-pads-and-rotors

Below you will find the process from the manual on how to replace the pads. Please let us know what you find.

Here is a guide to help you step by step to remove the rear calipers and instructions with diagrams below. Can you please shoot a quick video with your phone so we can see what's going on? that would be great. You can upload it here with your response.

https://www.2carpros.com/articles/how-to-replace-rear-brake-pads-and-rotors

Check out the diagrams (below). Please let us know if you need anything else to get the problem fixed.