Beneath their upholstery, car seats are padded with foam rubber. Over time, this rubber can tear and degrade, requiring repair. Many people simply replace the entire foam portion of the seat, which is very wasteful if the damage is not severe. It is much easier, cheaper and more environmentally friendly to repair the damaged section of the foam rubber, while leaving the rest intact. This process is much easier than most people would initially think.
Spread open the torn foam and remove any dirt or debris.
Spray in foam glue, making sure to coat both sides of the tear.
Hold the tear closed for a few minutes to allow the glue to set.
Let the glue cure overnight for full strength.
Cut out large damaged sections from the foam with a razor blade.
Obtain a new sheet of foam rubber from an upholstery supplier. It should be the same thickness as the foam used on the seat.
Cut the foam sheet into a patch that is the same shape as the foam you removed from the seat. You can use a razor blade for this, but an electric carving knife is much faster.
Spray foam glue on the back of the patch and the sides of the hole in the seat.
Press the patch into the hole and hold it in place for several minutes to let the glue bond.
Allow the glue to cure overnight for maximum strength.