I had a simular problem on a B2300 and it turned out to be the fuel vapor recovery system. There is a solenoid that holds pressure in the fuel tank and mine had gone bad. It my be your gas cap too. Just a thought
P0456 - EVAP Control System Leak Detected (Very Small Leak)
The PCM monitors the complete EVAP control system for the presence of a very small fuel vapor leak. The system failure occurs when a fuel vapor leak from an opening as small as 0.508 mm (0.020 inch) is detected by the EVAP running loss monitor test. Possible causes are:
- Very small holes or cuts in fuel vapor hoses/tubes.
- Loose fuel vapor hose/tube connections to EVAP system components.
- EVAP system component seals leaking (refer to Possible Causes under DTC P0442).
P0442 - EVAP Control System Leak Detected (Small Leak) possible causes:
- After-market EVAP hardware (such as fuel filler cap) non-conforming to required specifications
- Small holes or cuts in fuel vapor hoses/tubes
- Canister vent solenoid stays partially open on closed command
- Damaged, cross-threaded or loosely installed fuel filler cap
- Loose fuel vapor hose/tube connections to EVAP system components
- EVAP system component seals leaking (EVAP canister purge valve, fuel tank pressure sensor, canister vent solenoid (see post immediatly above), fuel vapor control valve tube assembly or fuel vapor vent valve assembly)
Where is the are these part located in the engine compartment (solenoid, fuel vapor hoses etc.) I have a friend that has an 03 ranger that we pulled the same code with my scanner. I saw that the evap solenoid was located near the brake line block. Just trying to help a friend out. BYO71 what was the final diagnosis of your issue? Thanks in advance for any help that you may be able to give.