Remove fuel tank on 95 Ford aerostar. It has a vapor leak we must repair a leak in vapor recovery system

The Evaporative emission system has a large leak allowing fuel vapors to escape to the atmosphere . There are hoses an a purge solenoid ,a vent solenoid ,charcoal canister to store fuel vapors in . The charcoal canister is located under the vehicle near the fuel tank an has vapor lines running to the front of the vehicle to where the engine draws in the vapors by the engine computer opening the purge solenoid ! Any of this vapor hose could have a hole (leak) ,the gas cap could be lose or bad . The fuel filler neck could be rusted through ! At the repair shop we hook up a smoke machine to the system an look for a leak like that ! easy !

ive seen this happen on new cars , but not on a 2k model , but might be same cause , if you do a code check you might see a vac canister fail on the readout , all new cars have a vapor recovery system that recovers the fuel vapor inside tank and burns it in engine , the vapors are collected in a canister then pulled into engine and burned off , this gets clogged up sometimes and needs replacement , the new gas pump nozzles have what is called a closed loop system , they need to sense a no pressure backfeed from gas tank when filling it in order to work , long and the short of it , gas nozzle won;t allow fuel in if vapor in tank builds up from a backed up canister

Hi,

Improve the Fixya.com experience for everyone by voting!

P0455 = Evaporative Emission Control System Leak Detected (gross leak)

What does that mean?

This indicates a fuel vapor leak or lack of purge flow in the EVAP control system. It means a large leak has been detected. The (EVAP) emission control system prevents the escape of fuel vapors from a vehicle's fuel system. Fuel vapors are routed by hoses to a charcoal canister for storage. Later, when the engine is running a purge control valve opens allowing intake vacuum to siphon the fuel vapors into the engine.
Symptoms

You likely won't notice any drivability problems.

Causes

A code P0455 most likely means one or more of the following has happened:

• A loose or improperly affixed gas cap
• A non-conforming gas cap (i.e. not factory/original brand)
• Other leak or damaged piece in EVAP system

Possible Solutions

With a P0455, the most common repair is to:

• Remove and reinstall the gas cap, clear the codes, and drive for a day and see if the codes come back.
• Otherwise, replace the gas cap, and/or
• Inspect the EVAP system for cuts/holes in tubes/hoses (you may hear a vacuum noise or smell fuel), repair if necessary

All the best

Ben

what codes?

The vacuum lines run from the canister to the intake manifold. One is the purge hose to deliver stored fuel vapor to the intake to be burnd when engine is warm and you are crusing at part throttle. The other line is the vacuum line to operate it.

Fuel Vapor Valve, Aerostar (4.0L Engine) The evaporative emission valve (9B593) uses a small orifice, 1.83mm (0.072 inch), that allows vapors to pass into the vapor line running forward to the evaporative emissions canister (EVAP canister) (9D653). This evaporative emission valve mounts directly into the fuel tank (9002) using a fuel vapor separator seal. Fuel vapors trapped in the sealed fuel tank are vented through the orificed evaporative emission valve. The vapors from the fuel tank leave the evaporative emission valve through a single vapor line and continue to the evaporative emissions canister in the engine compartment for storage.
-----------------------------------------------------
Fuel Vapor Canister Purge Regulator Valve, Aerostar, Ranger Removal and Installation

1. Disconnect wire harness from evaporative emission canister purge valve (EVAP canister purge valve) (9C915).
   

1. Disconnect wire harness from thermistor.
   

1. Disconnect evaporative emission canister purge valve assembly from fuel vapor canister and throttle body.
   

1. To install, reverse removal procedure.
   

-----------------------------------------------------------------

Removal & Installation
To Remove:

1. Properly relieve the fuel system pressure.
   
2. Drain the fuel tank through the filler pipe.
   
3. Support the fuel tank.
   
4. Remove or disconnect the following:
   
   
   
   • Negative battery cable
     
   • Filler neck
     
   • Shield and tank straps
     
   • Fuel lines and vapor hose from pump and tank
     
   • Electrical connection from fuel pump
     
   • Fuel tank
     
   • Fuel pump/sending unit assembly by turning the locking ring (located on top
     of the fuel tank) counterclockwise using a spanner wrench
     
   • Fuel pump from the fuel lever sending device

To Install:

1. Install or connect the following:
   
   
   
   • Fuel pump in tank with new seal around opening
     
   • Tank and connect fuel lines and vapor hose
     
   • Tank to the frame
     
     
     
     1. Torque to: 33 ft. lbs. (45 Nm)
     
     
   • Shield
     
   • Fuel filler neck and clamp
     
   • Negative battery cable
   
   
2. Refill the tank.
   
3. Run the engine and check for leaks.

View of the in-tank fuel pump assembly.

DTC P1455 - Substantial Leak or Blockage in Evaporative Emission Control System

The PCM monitors the complete EVAP control system for no purge flow, the presence of a large fuel vapor leak or multiple small fuel vapor leaks. The system failure occurs when no purge flow (attributed to fuel vapor blockages or restrictions), a large fuel vapor leak or multiple fuel vapor leaks are detected by the EVAP running loss monitor test with the engine running (but not at idle).

Check this possible causes:
After-market EVAP hardware (such as fuel filler cap) non-conforming to required specifications
Disconnected or cracked fuel EVAP canister tube, EVAP canister purge outlet tube or EVAP return tube
EVAP canister purge valve stuck closed
Damaged EVAP canister
Damaged or missing fuel filler cap
Insufficient fuel filler cap installation
Loose fuel vapor hose/tube connections to EVAP system components
Blockages or restrictions in fuel vapor hoses/tubes (items also listed under disconnections or cracks)
Fuel vapor control valve tube assembly or fuel vapor vent valve assembly blocked
Canister vent (CV) solenoid stuck open
Mechanically inoperative fuel tank pressure (FTP) sensor


Check for audible vacuum noise or significant fuel odor in the engine compartment or near the EVAP canister and fuel tank

Tell us news.

drain all the fuel you can from the tank, SAFELY using proper saftey equipment, place the vehicle on jack stands, disconnect the battery, place a jack under the tank, remove fuel cap, remove 3 screws holding filler neck to the inside of fuel filler door compartment, remove tank straps, remove driveshaft, lower tank slightly & remove fuel neck, wires, fuel couplings, lower tank & remove from vehicle. Carefully remove locking ring from the tank where it holds down the fuel pump asy, remove pump asy & replace components as needed, reassemble, check for leaks, road test vehcile

Hi,

P0455 indicates that the Evaporative Emission (EVAP) control system detected a large leak or no purge flow. has nothing to do with the exhaust, unless, the leaking hot exhaust gases burned up a hose of some other part of the EVAP system.

Thanks.

check fuel filter first. rate as fixed if this helps.

Steel Midship, Aerostar
Removal and Installation

1. NOTE: Make sure fuel tank (9002) is properly supported during removal and installation procedures.
   Drain fuel from fuel tank .

1. Loosen fuel tank filler pipe clamp.

1. Remove fuel tank heat shield (9A032) from vehicle.

1. Support fuel tank .

1. Remove bolt from rear fuel tank support strap (9092) and remove rear fuel tank support strap .

1. Remove bolt from front fuel tank support strap and remove front fuel tank support strap .

1. Partially lower fuel tank to gain access and remove feed and return lines from sender ports. To disconnect push connect fittings, refer to Push Connect Fittings in this section.

1. Remove electrical connector from sender unit.

1. Remove fuel vapor hose from evaporative emission valve (9B593) .

1. Lower fuel tank from vehicle.

The evap system ( fuel vapor recovery system ) , if there is a leaky hose, can let fumes out that can be detected in the cab. If you "top off" the fuel at the pump you can spill fuel into the charcoal canister meant for fuel vapors only. the vapor recovery system is behind the left rear tire.

Usually if there is a hose leak a check engine light will come on.

If you TOP OFF, don't. If you don't, good. Hope this helps.