Ok, so I have been chasing this and I want to figure it out. I replaced the purge valve, evap solenoid, gas cap and the gas filler tube. I am still seeing the warning and I’m not sure what to do. I can see that the fuel pump is rusty, any idea how I can tell if the o ring is leaking past the locking ring? I can’t hear any leaks and I can’t visually see anything wrong.

Here is my report.

www.BlueDriver.com
VIN: DECODED:
Model Year: Make: Model: Trim Level:
P0455 Repair Report
5GRGN23U95H133695
2005 Hummer H2 (Base)
2005 Hummer H2
Base
P0455 CODE DEFINITION:
• Evaporative Emission (EVAP) System
8 POSSIBLE CAUSES:
• ECM has failed
• Fuel filler cap is very loose, missing or the wrong part
• Fuel tank pressure sensor is damaged, disconnected or it failed • Fuel tank vapor line(s) is clogged, damaged or disconnected
• Fuel tank, fuel filler neck or fuel sending unit 'O' ring is leaking
• Purge solenoid is not opening (it may be damaged or sticking)
• Purge valve vapor line is clogged, damaged, or disconnected
• Vent solenoid is not closing (it may be damaged or sticking)
3 TOP REPORTED FIXES:
• Replaced Evaporative Emissions (EVAP) Canister Vent Solenoid/Valve
• Replaced Evaporative Emissions (EVAP) Canister Purge Solenoid/Valve • Replaced Fuel Filler Cap
13 FREQUENTLY REPORTED FIXES:
Disclaimer:
The Possible Causes outlined above may or may not be the cause of your vehicle trouble code(s) being triggered. The Reported Fixes listed are suggestions only, and a fix is not guaranteed by performing any of the above potential solutions. The trouble code summary data may help you pinpoint the type of repair facility that should be consulted. It is strongly recommended that you consult with a knowledgeable professional repair facility for proper diagnosis and repair of trouble code issues. This information is provided without warranty and is subject to the Terms of Use posted at www.lemurmonitors.com/eula.html. Reproduction of this information or any portion thereof constitutes infringement of copyright.
© Copyright 2018 Page 1

www.BlueDriver.com
VIN: DECODED:
Model Year: Make: Model: Trim Level:
P0455 Repair Report
5GRGN23U95H133695
2005 Hummer H2 (Base)
2005 Hummer H2
Base
13 FREQUENTLY REPORTED FIXES: (Continued)
• Replaced Charcoal Canister
• Replaced Fuel Tank Pressure (FTP) Sensor
• Replaced Vent Control Valve
• Replaced Fuel Pump / Sending Unit Assembly
• Replaced Fuel Tank Sending Unit O-Ring
• Replaced Evaporative Emission (EVAP) System Hose(s)/Line(s)
• Repaired Evaporative Emissions (EVAP) Canister Vent Solenoid/Valve Wiring • Replaced Fuel Filler Neck
• Replaced Powertrain Control Module (PCM)
• Replaced Canister Vent (CANV) Solenoid w/P0446
• Tightened Fuel Filler Cap
• Installed Fuel Filler Cap
• Replaced Fuel Tank
25 OTHER REPORTED FIXES:
• Repositioned Canister Vent Filter
• Installed Canister Vent Filter
• Replaced Charcoal Canister Hose(s)
• Repaired Charcoal Canister Hose(s)
• Replaced Crankshaft Position (CKP) Sensor w/P0300, P0352
• Repaired Crankshaft Position (CKP) Sensor Wiring w/P0300, P0352
Disclaimer:
The Possible Causes outlined above may or may not be the cause of your vehicle trouble code(s) being triggered. The Reported Fixes listed are suggestions only, and a fix is not guaranteed by performing any of the above potential solutions. The trouble code summary data may help you pinpoint the type of repair facility that should be consulted. It is strongly recommended that you consult with a knowledgeable professional repair facility for proper diagnosis and repair of trouble code issues. This information is provided without warranty and is subject to the Terms of Use posted at www.lemurmonitors.com/eula.html. Reproduction of this information or any portion thereof constitutes infringement of copyright.
© Copyright 2018 Page 2

www.BlueDriver.com
VIN: DECODED:
Model Year: Make: Model: Trim Level:
P0455 Repair Report
5GRGN23U95H133695
2005 Hummer H2 (Base)
2005 Hummer H2
Base
25 OTHER REPORTED FIXES: (Continued)
• Repaired Engine Wiring Harness w/P0300, P0352
• Repaired EVAP Canister Vent Hose
• Repaired Evaporative Emission (EVAP) System Hose(s)/Line(s) w/P0496 • Repositioned Evaporative Emissions (EVAP) Canister Vent Solenoid/Valve • Tightened Evaporative Emissions (EVAP) Canister Vent Solenoid/Valve
• Lubricated Evaporative Emissions (EVAP) Canister Vent Solenoid/Valve
• Cleaned Evaporative Emissions (EVAP) Canister Vent Solenoid/Valve
• Replaced Exhaust Gas Recirculation (EGR) Valve
• Replaced Exhaust Manifold w/P0300, P0352
• Repaired Fuel Filler Neck
• Repaired Fuel Injector Wiring w/P0102, P0200, P0300...
• Replaced Fuel Pump Module Seal
• Repaired Ignition Coil Wiring w/P0300, P0352
• Replaced Ignition Coil Wiring w/P0300, P0352
• Replaced Intake Manifold w/P0300, P0352
• Replaced Oxygen (O2) Sensor(s)
• Replaced Spark Plug Wire(s) w/P0300, P0352
• Replaced Spark Plug(s) w/P0300, P0352
• Cleaned Throttle Body
Disclaimer:
The Possible Causes outlined above may or may not be the cause of your vehicle trouble code(s) being triggered. The Reported Fixes listed are suggestions only, and a fix is not guaranteed by performing any of the above potential solutions. The trouble code summary data may help you pinpoint the type of repair facility that should be consulted. It is strongly recommended that you consult with a knowledgeable professional repair facility for proper diagnosis and repair of trouble code issues. This information is provided without warranty and is subject to the Terms of Use posted at www.lemurmonitors.com/eula.html. Reproduction of this information or any portion thereof constitutes infringement of copyright.
© Copyright 2018 Page 3

 

Without a smoke machine diagnosis, you will just be guessing. I would do the Canister solenoids if I was going to guess. That is the most common cause of your symptom.

 

Yeah I did already replace the solinoid and purge valve and gas cap and filler tube.

 

can you monitor the tank pressure, vent solenoid position and the purge solenoid position to see that they are working as they should?

are you having trouble filling the tank, going really slow?

Neal

 

Not sure if I can see live data for those on my scanner. I’ll check. I don’t seem to ever remember having trouble filling the tank. Any ideas what I can check?

 

You need to see the live data to get an idea of whats going on.

The vent solenoid should open and vent the tank through the carbon canister when shut off. The question about filling was to see if there may be an issue with the carbon canister. If you have to fill very slow then that's an indication that the carbon canister is plugging or the vent solenoid is not opening.

The fact that the ECM thinks that the tank is loosing vacuum tells us that the purge solenoid is being commanded to open and the vent solenoid is being commanded to close and the ECM is looking for the tank to go to a negative pressure and hold for a given amount of time. The tank is not holding the vacuum for the given time so the ECM is setting a P0455. We need to know the tank pressure is falling to a negative pressure when commanded to and that the vent solenoid is closing and not leaking allowing the pressure to rise when the ECM performs this test.

Without seeing the live data we really don't know where to start,

Neal

 

Take a walk around your rig after you park it, and let me know if you smell fuel?

 

I’ll do this in the morning. I’ll also look on my scanner and see if it has live data for those things. I don’t think so. It’s a obd2 scanner called bluedriver.

Mire on gas smell in the morning.

 

Sorry. Work has me so busy I can’t see straight. So I was trying to see if I could smell gas. I’ll be honest my sense of smell sucks... I thought I had gotten a wiff of gas fumes a few times before too so I am actually in the middle of pulling trim off to get some body and paint t work done. Well with the rear driver side wheel well I can see easily on top of the tank. It looked s little dark on the far side so I thought I’d see if it felt wet... well as soon as I touched the vent on the pump it fell off. The pump is rusted right through. This is most likely the problem. I know I have seen others stating same if the forum and on line.

Going to order a new pump and locking ring. If I remember right there are 1 or 2 sensors on top of the tank. Can anyone get me a part number or name? I’m searching for them. Might as well replace them too while I have the tank down.

 

Look here to find part numbers.... https://nemigaparts.com/cat_spares/epc/hummer/