I have the same problem with mine. What i found out is its the cable form the outside handle goes to a plastic piece that pivots and opens the door. On this piece the rivet holding it in gets rusted, and as you pull on the outside handle it stays in the opened position.
Once you start driving the doors automatically lock and because the rear hatch is still you cannot unlock the back door to close it.
The Fix - There is a small plastic square piece on the cover of the back door on the inside where the lock is. Take this out and use a flashlight to see the white plastic piece with the cable attached to at the back of the lock assembly.
Get a screwdriver and push this down, then unlock the door and the door with close. It is pretty easy.
I took the whole back panel off and used wd40 all over the lock and moved it manually until it freed itself and i haven't had a problem in about a month.
Mark
Ford Freestar was created in 2004.
( 26 U.S. gallons ) for a 2004 Ford Freestar
One reason a 2004 Ford Freestar may stall out is because of a water damaged PCM. This is a common problem with the 2004 Ford Freestar.
According to the 2004 Ford Freestar Owner Guide : ( 26.0 U.S. gallons )
how can ford freestar 2004 water pump be replaced
On a 2004 Ford Freestar : The transaxle ( transmission ) is located in the engine compartment on the drivers side . It is bolted to the " rear " of the engine
Switch on the center dashboard that says 'vent'.
On a 2004 Ford Freestar : 1-----2-----3 ( bank 1 ) 4-----5-----6 ( bank 2 ) front of vehicle > driver Bank 2 , sensor 1 would be close to the engine BEFORE the exhaust enters the catalytic converter
On
According to a website I was looking at : For a 2004 Ford Freestar ( 3.9 and 4.2 ) ( 15 city / 21 highway , miles per U.S. gallon )
firewall 1-----2-----3 4-----5-----6 front of Ford Freestar > driver
35 lbs