Ok like the title says I got a check engine light on my 2010 2dr today. I stopped by auto parts store to check code. It came up as P0455 which is [evaporative emission system leak detected gross leak/no flow]. I checked gas cap and cleared code then drove home 13+ miles I will cross my fingers that it does not come back. Has anyone had this code come up what was the cause of it and how did you fix it?

 

I get the same code all the time. I've been too lazy to really look into it. I changed gas caps and it's still there. I assumed I broke my charcoal canister but after visual inspection it looks ok. I cleaned out the little filter thingy on the charcoal canister and it made no difference. I assume I've got a crack in a vacuum line or something. I'll worry about it when emission time rolls around. Post up what you find.


PS. Here is why I haven't looked too far into it. Copied out of the MotorAlldata DTC diagnostic guide


P0455-EVAP PURGE SYSTEM LARGE LEAK





For a complete wiring diagram, refer to the Wiring Information . See: Diagrams\Electrical


•When Monitored: With the engine running, during a cold start test with the fuel level above 12%, ambient temperature between 4°C and 32°C (39°F and 89°F) and the fuel system in closed loop. The test runs when the small leak test is maturing.
•Set Condition: The Powertrain Control Module (PCM) activates the Evap Purge solenoid to pull the Evaporative system into a vacuum to close the Evaporative System Integrity Monitor (ESIM) switch. Once the ESIM switch is closed, the PCM turns the Evaporative Purge solenoid off to seal the Evaporative system. If the ESIM switch reopens before the calibrated amount of time, a large leak error is detected. Two Trip Fault. Three good trips to turn off the MIL.







Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. See: Powertrain Management\Computers and Control Systems\Testing and Inspection\Initial Inspection and Diagnostic Overview\Pre-Diagnostic Troubleshooting Procedure.

1. VEHICLE HISTORY AND SERVICE BULLETIN INVESTIGATION

1.Ignition on, engine not running.
2.With the scan tool, select View DTCs and record the related Freeze Frame data if any DTCs are present.
3.Whether or not any DTCs are Active you will want to check the following items which may assist in repairing the customer's complaint successfully.
4.Check the vehicle's repair history.
5.If the vehicle has a repair history that pertains to the customer's current complaint, review the repair.
6.Inspect the vehicle for any aftermarket accessories that may have been installed incorrectly.
7.Check for any service bulletin(s) related to the customer's complaint or DTCs.
8.If a service bulletin applies, follow the instructions of the service bulletin.

Choose the following scenario that best applies.

The service bulletin repaired the customer's complaint.


•Testing complete.

A DTC is present, no service bulletins apply or the service bulletin didn't repair the customer's complaint.


•Go To 2

2. ACTIVE DTC



NOTE: Since a hot vehicle can conceal a leak, it is best to perform this test at room temperature.
NOTE: A loose gas cap could have caused this DTC to set. Make sure gas cap is tight and in good condition. Make sure the gas cap meets OEM specifications.
1.Start the engine.
2.Allow the engine to idle.
3.Using the scan tool, perform the ESIM FORCED MONITOR TEST. Allow the test to complete.
4.With the scan tool, select View DTCs.

Is the DTC Active at this time?

Yes


•Go To 3

No


•Perform the INTERMITTENT CONDITION diagnostic procedure. . See: Powertrain Management\Computers and Control Systems\Testing and Inspection\Initial Inspection and Diagnostic Overview\Intermittent Condition Test

3. EVAPORATIVE SYSTEM INSPECTION
Inspect the Evaporative System for any of the following conditions:


•Holes or cracks
•Loose seal points
•Damaged or missing components
•Incorrect routing of hoses and tubes
•Loose or missing Fuel Cap
•Damaged or missing Fuel Cap seal
•Improper installation of the Fuel Cap
•Damaged Locking tabs on the Fuel Cap and/or filler tube
•Damaged seal points on the Fuel Cap and/or filler tube

Were any of the above conditions found?

Yes


•Repair as necessary.
•Perform the POWERTRAIN VERIFICATION TEST. See: Verification Tests\Powertrain Verification Test.

No


•Go To 4

4. VERIFY EVAPORATIVE EMISSION LEAK



WARNING: Keep lit cigarettes, sparks, flames, and other ignition sources away from the test area to prevent the ignition of explosive gases. Keep the test area well ventilated. Failure to do so may result in possible serious or fatal injury.
1.To continue testing you will need Evaporative Emission Leak Detector (EELD) 8404A.

NOTE: The fuel tank should have between 20% and 80% of fuel tank capacity to properly test the Evaporative system.
2.Connect the red power lead of the EELD to the battery positive terminal and the black ground lead to battery negative terminal.
3.Block the vent hose of the canister if using the service port.
4.Connect shop air to the EELD.
5.Set the smoke/air control switch to AIR.
6.Insert the tester's AIR supply tip (clear hose) into the appropriate calibration orifice on the tester's control panel (based on DTC leak size).
7.Press the remote smoke/air start button.
8.Position the red flag on the air flow meter so it is aligned with the indicator ball.
9.When the calibration is complete, release the remote button. The EELD flow meter is now calibrated in liters per minute to the size leak indicated by the DTC set in the PCM.
10.Install the service port adapter 8404-14 on the vehicle's service port and block the vent hose of the Evap Canister (if equipped) or install adapter 8404-ADP into the filter line.
11.Connect the Air supply hose from the EELD to the service port (if equipped) or to the adapter 8404-ADP.
12.Press the remote button to activate AIR flow.

NOTE: Larger volume fuel tanks, lower fuel levels or if the vehicle is equipped with a Flow Management Valve may indicate high flow and will require 4 to five minutes to fill.
13.Compare the flow meter indicator ball reading to the red flag.
14.ABOVE the red flag indicates a leak present.
15.BELOW the red flag indicates a sealed system.

Is the indicator ball above the red flag?

Yes


•Go To 5

No


•Refer to the Freeze Frame data recorded in step 1. If the data indicates that the vehicle was in motion when the DTC was set, verify that all hoses are properly connected.
•Perform the POWERTRAIN VERIFICATION TEST. See: Verification Tests\Powertrain Verification Test.

5. EVAPORATIVE EMISSION LEAK DETECTION



NOTE: A thorough visual inspection of the Evaporative system hoses, tubes and connections may save time in your diagnosis. Look for any physical damage or signs of wetness at connections. The strong smell of fuel vapors may aid diagnosis also.
1.To continue testing, you will need Evaporative Emissions Leak Detector (EELD) 8404A.
2.Remove the Air supply hose from the service port (if equipped) or from the adapter 8404-ADP.
3.Connect the SMOKE supply tip (black hose) to the service port (if equipped) or to the adapter 8404-ADP.
4.Set the smoke/air control switch to SMOKE.

NOTE: The flow meter indicator ball will not move in the smoke mode.
5.Press the remote smoke/air start button.

NOTE: Make sure that smoke has filled the Evaporative system by continuing to press the remote smoke/air start button, remove the vehicle fuel cap and wait for the smoke to exit. Once smoke is indicated reinstall the fuel cap.
NOTE: For optimal performance, introduce smoke into the system for an additional 60 seconds; continue introducing smoke at 15 second intervals, as necessary.
6.While still holding the remote smoke/air start button, use the white light 8404-CLL to follow the Evaporative system path and look for the source of the leak indicated by exiting smoke.
7.If a leak is concealed from view (i.e., top of fuel tank), release the remote smoke/air start button and use the ultraviolet (UV) black light 8404-UVL and the yellow goggles 8404-20 to look for residual traces of dye that is left behind by the smoke.
8.The exiting smoke deposits a residual fluid that is either bright green or bright yellow in color when viewed with a UV light.

NOTE: The Evaporative System is divided into three zones. A leak from any of these zones can cause this DTC to set. The lists below specify the possible leak points in that specific zone. For further assistance see the Zone Identification Charts below.






ZONE 1

•Fuel Cap
•Recirculation Check Valve
•Vapor Recirculation Line
•Signal Vapor Line for FVM
•Flow Management Valve
•Fuel Tank to Canister Vapor Line
•Fuel Tank Vent (Check Valve)
•Vapor Line to Canister
•Flow Control Orifice
•Control Valve
•Liquid Trap
•Fuel Tank
•Check valve
•Fuel Fill Tube to Tank connector
•Fuel Fill Tube






ZONE 2

•Filter
•Evaporative System Integrity Monitor Switch
•Canister Vent Line
•Evaporative Canister
•Chassis Purge Valve
•Fuel Tank to Canister Vapor Line connection
•Evap Purge solenoid connection





ZONE 3

•Evaporative Purge Vacuum Line
•Connection to Chassis Line
•Connection to Canister
•Chassis Purge Line
•Evap Purge solenoid vacuum line
•Connection to Evap Purge solenoid harness
•Chassis Evaporative Purge line connection to Engine Vacuum
•Evap Purge Valve
•Service Port

NOTE: Carefully inspect the vent side of the Evaporative Canister. Due to the filtering system in the canister the smoke may not be as thick. Introducing smoke into the filtered side of the canister may assist in locating the leak.

Select the appropriate response from the list below:

A leak was found at the gas cap or fuel filler tube


•Go To 6

A leak was found in one or more of the Evap System zones


•If the leak is at a hose connection, remove the hose then reconnect the hose and check for a leak again. All other leaks repair as necessary.
•Perform the POWERTRAIN VERIFICATION TEST. See: Verification Tests\Powertrain Verification Test.

No leaks were detected


•Go To 7

6. LEAK AT GAS CAP

1.Remove the SMOKE supply tip (black hose) from the service port (if equipped) or to the adapter 8404-ADP.
2.Install Leak Check Adapter 8382 (1/4 turn cap) or Fuel Tank Adapter 6922 (screw on cap) and Leak Check Adapter 8399 (secondary seal depressor) and repeat step 5.

NOTE: The gas cap adapter is being used as a known good cap.

Was a leak found at the gas cap adapter?

Yes


•Replace the Fuel Filler tube assembly.
•Perform the POWERTRAIN VERIFICATION TEST. See: Verification Tests\Powertrain Verification Test.

No


•Replace the gas cap.
•Perform the POWERTRAIN VERIFICATION TEST. See: Verification Tests\Powertrain Verification Test.

7. EVAP PURGE SOLENOID OPERATION



NOTE: After disconnecting the Evap Purge solenoid vacuum connections, inspect the lines and solenoid for any signs of contamination from the Evap Canister.
1.Turn the ignition off.
2.Disconnect the Evap Purge solenoid Vacuum hose at the Throttle Body.

NOTE: You are disconnecting the vacuum line at the Throttle Body so you are not disturbing the vacuum connection at the Evap Purge solenoid.
3.Press the remote smoke/air start button on the EELD.
4.While holding the remote smoke/air start button, check to see if smoke is exiting the Evap Purge solenoid vacuum hose at the Throttle Body. This indicates that there is a leak internal to the purge valve.

NOTE: Below is an optional method of checking the purge valve for leaks if the EELD is unavailable.
5.Turn the ignition off.
6.Disconnect the vacuum hoses at the Evap Purge solenoid.
7.Using a hand vacuum pump, apply 10 in Hg to the "CAN" side of the Evap Purge solenoid.

NOTE: Monitor the vacuum gauge for at least 1five seconds.

Is smoke visible from the Evap Purge solenoid vacuum hose if using the EELD or will it not hold a vacuum?

Yes


•Replace the Evap Purge solenoid.
•Perform the POWERTRAIN VERIFICATION TEST. See: Verification Tests\Powertrain Verification Test.

No


•Go To 8

8. EVAP SYSTEM MONITOR SWITCH

1.Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Evap System Monitor Switch and the Powertrain Control Module (PCM).
2.Look for any chafed, pierced, pinched or partially broken wires.
3.Look for broken, bent, pushed out or corroded terminals.
4.Verify that there is good pin to terminal contact in the Switch and the Powertrain Control Module connectors.
5.Perform any Technical Service Bulletins that may apply.

Were any problems found?

Yes


•Repair as necessary.
•Perform the POWERTRAIN VERIFICATION TEST. See: Verification Tests\Powertrain Verification Test.

No


•Replace the ESIM Switch.
•Perform the POWERTRAIN VERIFICATION TEST. See: Verification Tests\Powertrain Verification Test.

 

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Thanks for the info I will post if it happens again. As well as what solves the problem for me.

 

Well new update I had my dash yelling at me saying gas cap the other day checked it and it was secure. then to day I got a check engine light with P0455 code again going to change gas cap tomorrow and clear code and go from there.

 

Check the lines to your evap canister - make sure they're secure. Also check the connections to the module in engine bay. Either one of these could throw a GASCAP code. You may even have a leak in the vacuum line to the EVAP can.

 

I went thru MONTHS of the dealer trying to fix this problem on mine and they NEVER got it fixed. The first heatwave of this year fixed the problem lol. O and the dealer WONT get the same code as u. Apparently po455 is a code for The mini van the service manager told me and showed me that they come up with a different code when they scan it. I forget what it was but it wasn't p0455. Good luck, I got thousands in new parts even a new gas tank for free from the dealer tho! Lmao

Sent from my obama monitoring device

 

Good to know I changed out the gas cap and cleared the code. I am going to wait and see if it comes back. I am also going to check all lines and make sure every thing looks good. If it comes back I will go to the dealer I am still under warranty so hopefully it is some thing that would be covered.

 

Well that did not last long Just replaced gas cap on sat got check engine light this morning. Have yet to check it but pretty sure its p0455, it will be off to the dealer this week I will have info as to what was the problem once I know.

 

When you go to the gas station, do you have problems filling your tank? Lately when getting gas I can't use the lock tab on the pump because it will go for a gallon or so then shut off, like it's building pressure in the filler tube. I'm guessing I should investigate my P0455 sooner then later. Keep me posted. I'll be curious what the dealer says.

 

I mentioned before the GASCAP code doesn't necessarily mean the actual gascap is the problem. It's more than likely one of your vacuum lines has a leak, the evap canister has a leak, or a seal is broken. When I broke off my evap canister on the trail, I got a GASCAP code until I replaced it, including the o-ring seal between the canister and the vacuum pump.