Technical Getting a P0456 "Permanent" code. Can't clear CEL either with my reader

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Technical Getting a P0456 "Permanent" code. Can't clear CEL either with my reader

LuvMyPop

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I have changed the gas cap out for a new one, didn't help. Its a 2013 Pop. Any ideas before I have to bring it in? What could be failing after the gas cap didn't fix the code?
 
Hi :)

@rrrsma had similar..

It was a minor split in the EVAP system


Click on their username to read more
Thank you for your comment. Do you know where the split was exactly ? Can you provide a picture with the exact location ? I replaced many components in the EVAP system including the most expensive one like the EVAP Canister and also the purge valve, Also verified with the smoke machine the entire system but could not find any leak whatsoever. Check engine light sometimes goes off by itself during colder weather and I am assuming it's just because there is not much pressure building in the EVAP. Any further help is really appreciated
 
Thank you for your comment. Do you know where the split was exactly ? Can you provide a picture with the exact location ? I replaced many components in the EVAP system including the most expensive one like the EVAP Canister and also the purge valve, Also verified with the smoke machine the entire system but could not find any leak whatsoever. Check engine light sometimes goes off by itself during colder weather and I am assuming it's just because there is not much pressure building in the EVAP. Any further help is really appreciated
Oh wow.... this has me worried to say the least.
 
Is your check engine light still on? Was it ever on??

If all you have is a permanent code that does not mean anything is wrong with your car. Permanent codes in 2010 and newer cars can be ignored. They do not mean anything IS wrong with your car. They mean something WAS wrong with your car.
 
Is your check engine light still on? Was it ever on??

If all you have is a permanent code that does not mean anything is wrong with your car. Permanent codes in 2010 and newer cars can be ignored. They do not mean anything IS wrong with your car. They mean something WAS wrong with your car.

Not if you cannot get it to 'stay gone'

If it clears for a minute..then returns
It wants investigating

Always a chance your OBD kit is not communicating properly I suppose..
 
Not if you cannot get it to 'stay gone'

If it clears for a minute..then returns
It wants investigating

Always a chance your OBD kit is not communicating properly I suppose..

On cars 2010 and newer You cannot clear permanent codes with a scanner or battery disconnect. So they are not "Popping back up" they are just never leaving. That they are present does not mean you have a fault. Means you HAD a fault and the codes are there just to verify that the fix has done correctly. "Permanent" is a bad name for them as it confuses and scares people. A better name would have been 'Verification" codes.

Now you are completely correct if it is a "pending" or "Confirmed " code that pops up right away yea that still needs a fix.

But if all OP is seeing is a Permanent code. Stop throwing money at it because there is nothing wrong.
 
Here is a good article on Permanent DTC's. The last line is the key to know:


" The presence of a Permanent DTC(s) without an illuminated MIL is an indication that the on-board monitoring system has not yet completed its verification. After repair, the remaining Permanent DTC corresponding to the repair can be treated as a P1000. DO NOT attempt to diagnose or repair a Permanent DTC(s) without a corresponding customer complaint unless the vehicle is rejected during an Inspection/Maintenance (I/M) inspection. "

And a person's OCD with having codes in thier car is not a good enough excuse! LOL
 
Is your check engine light still on? Was it ever on??

If all you have is a permanent code that does not mean anything is wrong with your car. Permanent codes in 2010 and newer cars can be ignored. They do not mean anything IS wrong with your car. They mean something WAS wrong with your car.
Yeah CEL was on, I cleared it, off so far.
 
On cars 2010 and newer You cannot clear permanent codes with a scanner or battery disconnect. So they are not "Popping back up" they are just never leaving. That they are present does not mean you have a fault. Means you HAD a fault and the codes are there just to verify that the fix has done correctly. "Permanent" is a bad name for them as it confuses and scares people. A better name would have been 'Verification" codes.

Now you are completely correct if it is a "pending" or "Confirmed " code that pops up right away yea that still needs a fix.

But if all OP is seeing is a Permanent code. Stop throwing money at it because there is nothing wrong.
I didnt do any repairs other than change the gas cap out. So far, the CEL is off after I cleared the code with my BAFX bluetooth scan tool.
 
So all you have to wait for now is your EVAP monitor to run (it may have already, you know how to check those?). It will either Run and give you a pending code, then you have more to fix. Or it will run and you will not have any codes and that means you have fixed it. But you will still have a permanent code either way so just ignore that.
 
So all you have to wait for now is your EVAP monitor to run (it may have already, you know how to check those?).
The EVAP monitor is from the onboard computers a.k.a the CEL? Or is it something else I use to check? Thanks...
 
Yea the monitors are tests the ECU performs on the various systems so they are stored along with the codes in the ECU.

The Codes you see are actually derived from the Monitors to some degree. The Evap Monitor might go through 3 tests and it uses the parameters of the corresponding codes in order to see if the test is pass of fail.

So for an Evap Monitor it will go through the parameters for:
P0440 - Leak
P0455 - Gross Leak
P0456 - Small leak

If any of those fail you get a pending code and eventually a check engine light
If they pass then the monitor just shows "Complete" or "Ready" . That means the tests were passed with no errors.

On your scanner they might be shown under an "Emissions" menu or an "I/M" menu for Inspections / Maintenance. Or some even use the nomenclature "Smog Test"
 
Is your check engine light still on? Was it ever on??

If all you have is a permanent code that does not mean anything is wrong with your car. Permanent codes in 2010 and newer cars can be ignored. They do not mean anything IS wrong with your car. They mean something WAS wrong with your car.
Light is still on. Sometimes when it's colder outside it takes a bit longer for the check engine light to come back on but eventually it turns back on showing the same code.
 
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