ok i put my parking lights in and one of them dosent stay on...i belive its the connection between the bulb n the port like its loose, seems like the bulb is too small, but the otha one does work. any ideas??

 

check your bulb size and also make sure that you have the socket correctly placed in there. those things are pain sometimes.

 

yes if the bulb seems "too small" it might be so. Pull the bulb, check the owners manual to verify the correct size.

Another thing - pull the bulb out and check if the contacts inside for any damage or "looseness". On sockets such as the side bumper light (where the bulb snaps in) you could use a small screwdriver to pry out the contacts slightly so that the bulb will snap in snug. On sockets that are spring loaded (such as brake or reverse lights) check to see if the spring isn't stuck compressed - the spring pushes the socket contacts up to the bulb.

Also, even if it's the correct bulb, and the filament looks good, if it's an old bulb it might be on it's way out. Bulbs arent' that expensive so better to replace than to guess.