On my 8P ive got a intermittent problem with the drivers side door, when im shutting it sometimes it bangs and only closes on the first latch but it wont full shut, if i try and close it a few times it bangs more times then it finally shuts, what could this be? when i sprayed some wd40 in the lock it didnt do it for a while but now its back again, was terrible this morning when it was frozen it just wouldnt shut for ages.