I have a 2001 v70 24t and the fuel filler door came off

Possible causes Missing or loose fuel cap Incorrect fuel filler cap used Fuel filler cap remains open or fails to close Foreign matter caught in fuel filler cap EVAP canister or fuel tank leaks EVAP system hose leaking Fuel tank leaking

its all 1 unit,
http://www.autopartswarehouse.com/shop_years/dodge-caravan-fuel-filler-neck-2001.html

2001 2002 Dodge Caravan Grand Caravan Voyager Fuel Tank Filler Neck...

P0456 DODGE - EVAP System Small Leak
As you see form the list there is not a single problem that causes this code to set.
Possible causes- Missing or loose fuel cap
- Incorrect fuel filler cap used
- Fuel filler cap remains open or fails to close
- Foreign matter caught in fuel filler cap
- EVAP canister or fuel tank leaks
- EVAP system hose leaking
- Fuel tank leaking

Read more: http://engine-codes.com/p0456_dodge.html#ixzz1xQr2MVRf

P0455 NISSAN - EVAPorative Emissions Control System Gross Leak Detected. Possible causes - Missing or loose fuel cap (most common)
- Incorrect fuel filler cap used
- Fuel filler cap remains open or fails to close
- Foreign matter caught in fuel filler cap
- EVAP canister or fuel tank leaks
- EVAP system hose leaking
- Fuel tank leaking (not common)

P0455 - Evaporative Emission Control System Leak Detected (Large Leak). Possible causes - Missing Fuel cap
- Incorrect fuel filler cap used
- Fuel filler cap remains open or fails to close
- Foreign matter caught in fuel filler cap
- Incorrect fuel tank vacuum relief valve
- Leak is in line between intake m

Possible solution - Retighten or replace fuel tank filler cap
- Replaced damage or leaking EVAP canister

Most cars have an emergency fuel filler door release somwhere in the trunk. Look for some kind of pull cord close to the area of the outside fill door.

open the fuel door remove screws for filler remover plastic filler you now have access to fuel door & hinge assemble

Remove fuel tank filler cap.

Push back release rod - 9 - by operating remote control unlock and remove bolt - 2 -.

Remove rubber part - 8 - from tank filler flange and swivel out tank flap unit - 1 - from side panel - 7 -.Assembly piece - 4 - and actuator - 6 - is installed.

• Install tank flap unit - 1 - (rubber part rolled up) with hinge side first.
• Bolt tank flap unit - 1 - and assembly piece - 4 - with bolt - 2 -.

Tightening torques: Bolts - 2 - 1.5 Nm

• Remove side luggage compartment trim.
• Disconnect harness connector at actuator - 6 -.
• Remove actuator - 6 - using special tool Socket wrench T 10010 from angled mounting bracket.
• Remove actuator - 6 - together with release rod - 9 - from seal - 5 - and assembly piece - 4 -.

Installing
Installation is reverse of removal.
Tightening torques: Bolts for actuator - 6 - 1.5 Nm .

IT SOUNDS LIKE IT IS TIME TO REPLACE HOLDER BEHIND FUEL DOOR EVEN IF YOU BREAK IT OFF TO OPEN ITS ONLY A FEW BUCKS TO REPLACE

check the connecting cable to the fuel lid. may be it's damaged.