I just used Turlte wax carpet and upholstery cleaner and it look brand new now. just spay it on and scrub! If you have a moon roof....make sure you open the roof so you can get the area of liner that is hidden when it is closed. When you spay it on, scrub it until the foam disappears. It worked like a charm! I would be careful about the staem cause like the other peeps said...it might loosen the liner.
<img src='http://img145.echo.cx/img145/8840/mack21876zl.jpg' border='0' alt='user posted image' />