@dar124;My check engine light came back on yesterday, exactly a week after changing the Leak Detection Pump and gasket. I checked and verified that it's the P0456 code again.
So I've changed the gas cap, the Vapor Canister Purge Valve and now the Leak Detection Pump. Any suggestions as far as what to look at changing out next for this code??
Usually this P0456 code is caused by an incorrect or faulty gas cap. Filling the fuel tank with the engine running could conceivable cause this code as well or if the cap wasn't properly tightened. Any of the following could also be the cause:
- A small leak in any of the EVAP hoses or fuel tank hoses
- A small leak in the purge valve or vent valve
- The EVAP Canister may be leaking
First, using a scan tool activate the vent solenoid, sealing the system. Then monitor the fuel tank pressure (FTP) sensor. If the system is sealing properly, the number will stay consistent. If is isn't, the pressure sensor will show that as well. If the system slowly leaks, use a smoke machine and watch for smoke exiting the system at any EVAP component. Any where there is smoke exiting the system, that is the faulty component. Do not pressurize the EVAP system with air pressure. Doing so can damage the purge and vent solenoids in the system.
If you want to solve the problem, I'd surmise that a smoke test, at a reputable shop, is probably you're best bet at this point.Ok, I was trying to replace some of the "easier" or cheaper items hoping to fix this myself. But it may be time to have this taken in somewhere to have a smoke test done on it as it seems like it might be one of the EVAP hoses leaking. When I was changing the Leak Detection Pump and gasket I looked at some of the hoses under there and none had any obvious holes or tears. Not sure how easy those lines would be for me to replace anyway.
If you want to solve the problem, I'd surmise that a smoke test, at a reputable shop, is probably you're best bet at this point.
That would have been one of the first things I tried for this code.So ... I'm back at it at least for a little bit longer trying to get rid of this P0456 code!! This past weekend I replaced the Vapor Canister on the Commander. I figured this was the last piece that I could easily replace on my own with out taking it into a shop. I removed the battery cable to clear the check engine light and it's been off since Sunday, so fingers crossed!! I've got to travel for work tomorrow, so I'll be putting some miles in and at least one tank of gas.
If it eventually comes back on, I'm also considering purchasing (another) new gas cap. But this time I'll make sure it's a genuine Mopar cap, like this one https://www.moparpartsgiant.com/oem-jeep-gas_cap.html?Make=Jeep&Model=Commander&Year=2006&Submodel=&Filter=()
I'll post back with any updates!!
That would have been one of the first things I tried for this code.
@dar124; It says right in the product description it's a Genuine MOPAR part with a MOPAR part number, that's guaranteed by Mopar's factory warranty; I'm kind of curious what made you think otherwise?Yep, it was one of the first things I replaced too. I swapped the gas cap out with this https://www.moparpartsgiant.com/oem-jeep-gas_cap.html?Make=Jeep&Model=Commander&Year=2006&Submodel=&Filter=()
But I wasnt 100% sure it was a Mopar cap since I got it from Amazon. If the Check Engine light comes back on, I figured I'd get one from a Mopar parts website or from the dealership.
|Part Description||CAP Fuel Filler|
|Manufacturer||Mopar. This genuine Mopar part is guaranteed by Mopar's factory warranty.|
It had been a while since I bought the replacement cap and looked at its description. Just the fact that it was from Amazon, made me wonder.@dar124; It says right in the product description it's a Genuine MOPAR part with a MOPAR part number, that's guaranteed by Mopar's factory warranty; I'm kind of curious what made you think otherwise?
Mopar Part No.: 52102464AC
Part Description CAP Fuel Filler Replaced By 52030433AB Manufacturer Mopar. This genuine Mopar part is guaranteed by Mopar's factory warranty.