Getting 404

Hi, you send me this to add to my permalinks –

/permalink;/%postname%/%post_id%

However, when clicking the actual car to pull up that information – it goes to 404 that the individual car ad cannot be found. Is the word “permalink” supposed to be changed to something?

I get the 404 on this URL structure – the ad will not display.
http://mywebsite.com/autos/permalink;/cars-for-sale/2001-ford-forucs-gas-saver

http://wordpress.org/extend/plugins/car-demon/