I cant unlock the trunk on my 1986 300E unless I unlock all the doors I have two different keys and neither of them work any one know of common problems.

It sounds like you have a trunk lock tumbler problem. You may have to order a new tumbler. (They have to be ordered from a dealer and you have to give ID and proof of ownership.)

Dave,

You say you only have two keys...
Do you have the square keys or the round keys? Mercedes has got service keys (the round ones) and these keys are not able to (un)lock the trunk and dash compartment...

...just a thought...

greetingz,