i had this problem as well on mine and after using the search engine on this site it brought me to a really great write up on how crappy our stock actuators are there like 20 cent pieces of crap that get caked up with gunk on the inside and eventually bind, anyway you nee to pull them out take the apart and refurbish them theres a write up @ http://gc.dsm.org/faqs/doorlocks.htm tells you exactly what you need to do to fix the problem or you can take the less painless way out and buy aftermarket ones, all depends on the person, good luck and hope this helps!