UGH P0456!! - Toyota Yaris Forums

yaris2010RS · 10-20-2011, 04:47 PM

so i officially hate this code! it has been the only issue on my moms 2001 camry and now my yaris has it.

i know its defined to a small leak detected in the evap system. and no its not the gas cap (like was on the camry many many times), it came on once before when i was just under half a tank and now again this morning (just under 3/4 tank)

does anyone have a good place to start checking for an issue? i find it only happens after the car has been drenched with water (first time was the morning after a car wash that night and this last time was after a wicked rain storm all night) could it be an electrical issue or is this just coincidence?

after searching the fourm i know a few other members have had this code come up, what was the route of the cause?

CTScott · 10-20-2011, 05:34 PM

It can be:

-Fuel cap (loose)
- Leakage from EVAP line (Canister - Fuel tank)
- Leakage from EVAP line (Purge VSV -
Canister)
- Canister pump module
- Leakage from fuel tank
- Leakage from canister

Is this happening on your 2010?

yaris2010RS · 10-20-2011, 06:17 PM

yep its on my 2010..... i want to take it to the dealership but not sure if it could have been caused by any of my mods (header)

this weekend i will remove header and intake and take it in if i cant find the issue

CTScott · 10-20-2011, 07:33 PM

Not the header, but check the vacuum purge valve hoses that are by the intake.

yaris2010RS · 10-20-2011, 08:25 PM

by the intake or on the intake? (run near it on connected to it?)

could water be the issue here? maybe on purge valve?

CTScott · 10-20-2011, 08:35 PM

Quote:

Originally Posted by yaris2010RS

by the intake or on the intake? (run near it on connected to it?)

could water be the issue here? maybe on purge valve?

On the OEM intake it is the cube that is attached to the intake tube, near the MAF sensor. It has two vacuum hoses and a connector going to it. I would start there and work in both directions checking the vacuum hoses.

Water wouldn't cause the 0456 unless it's water getting into fuel overflow and plugging up the charcoal canister. There was a TSB on that issue on 07's, but that was fixed by 08.

yaris2010RS · 10-20-2011, 09:06 PM

Quote:

Originally Posted by CTScott

On the OEM intake it is the cube that is attached to the intake tube, near the MAF sensor. It has two vacuum hoses and a connector going to it. I would start there and work in both directions checking the vacuum hoses.

Water wouldn't cause the 0456 unless it's water getting into fuel overflow and plugging up the charcoal canister. There was a TSB on that issue on 07's, but that was fixed by 08.

i will check the cube and hoses. if it doesnt come on in the morning i will go back to the coin wash and hose it down and see.

would a kinked hose cause the 0456? or would it have to be a leak? under what conditions does that line have a vacuum in it? (while engine is running or after engine is off it stores the pressure?)

CTScott · 10-20-2011, 09:10 PM

It gets measured 5 hours after the vehicle is powered off. A kink wouldn't do it, it has to be a leak.

Leak detection pump creates negative
pressure (vacuum) in EVAP system and
EVAP system pressure measured.
Reference pressure measured at start
and at end of leak check.
If stabilized pressure higher than second
reference pressure, ECM determines
that EVAP system has small leak.

yaris2010RS · 10-20-2011, 09:19 PM

lol so its not as easy as turning the car on and feeling for a leak. lol

it consideres it a small leak so ill never find it. look like header and intake are coming out and its going into the dealer ship

CTScott · 10-20-2011, 09:28 PM

Quote:

Originally Posted by yaris2010RS

lol so its not as easy as turning the car on and feeling for a leak. lol

it consideres it a small leak so ill never find it. look like header and intake are coming out and its going into the dealer ship

Definitely not an easy thing to trouble shoot, unless it is just a loose fitting vacuum hose.

yaris2010RS · 10-20-2011, 09:35 PM

Quote:

Originally Posted by CTScott

Definitely not an easy thing to trouble shoot, unless it is just a loose fitting vacuum hose.

lol, i know if u say its not easy to do im not even gonna attempt it.

are you sure there was a TSB on the 07? i searched but couldnt find anything

CTScott · 10-20-2011, 09:40 PM

It is T-EG048-07, but it is not for DTC P0456, it is for DTCs P043E,
P043F, P2401, P2402, and P2419.

yaris2010RS · 10-20-2011, 09:50 PM

HA! and i dont have those so its off to the dealer i go :p. only thing is ill need to wait till i get a chance to take intake and header out.

so the computer only scans the evap system 5 hours after the car has been turned off? so as long as i resist the urge to go out tonight in the morning the system would have been tested? (i can confirm this after with my scan tool and it displaying a run in relation to the evap) and if its not on in the morning that means i have a intermittent leak?

CTScott · 10-20-2011, 09:55 PM

Correct.

yaris2010RS · 10-20-2011, 09:59 PM

OMG THATS SO GONNA SUCK!!!! i really hope to god its either on in the morning or never on again.......

thanks CTScott for all your help

yaris2010RS · 10-21-2011, 08:13 AM

so this morning the engine light was not on. i ran the scan tool anyways and found the car had not run the evp system check over night(probably due to the c02 check not being preformed while i was drived the night before)

im now at school and its another +5 hours till i go out to my car so i will see then if the check was run and if it passed or not.

just thought id give a quick update

yaris2010RS · 10-24-2011, 11:13 AM

since no one ever does this, ill update this.

*****issue seems to have been resolved, anyone with a after market intake should check for this*****

000.jpg

apparently the Ziptie i had used to hold the purgevalve in place failed and the entire thing fell to where my shifter linkages were and when it got hit it cracked.

this part is 139.99 from the dealership (i got one free off a wrecked corolla which is a different part # and looks different but it seems to be working.)

when i get home from school today i will post picks of the old valve and hopefully tonight the computer will run the evap test and throw no codes

fingers crossed

jemmah · 12-04-2012, 10:50 AM

I've got a 2007 Yaris with 200k miles. I've had a p0456 code twice over the years. Both times I OVER filled the fuel tank. Both times the code would show up the next morning. If you over-filled this could be the problem. Please check this situation first before you start tearing everything apart!! I assume there was fuel flow into the charcoal canster and the by-pass opened.

10-20-2011, 04:47 PM	#1
yaris2010RS View User's Garage Drives: no-longer-boosted '10 Yaris Join Date: Nov 2009 Location: Angus, Ontario Posts: 1,891	UGH P0456!! so i officially hate this code! it has been the only issue on my moms 2001 camry and now my yaris has it. i know its defined to a small leak detected in the evap system. and no its not the gas cap (like was on the camry many many times), it came on once before when i was just under half a tank and now again this morning (just under 3/4 tank) does anyone have a good place to start checking for an issue? i find it only happens after the car has been drenched with water (first time was the morning after a car wash that night and this last time was after a wicked rain storm all night) could it be an electrical issue or is this just coincidence? after searching the fourm i know a few other members have had this code come up, what was the route of the cause? __________________ If it has boobs or wheels sooner or later your gonna have problems with it

10-20-2011, 05:34 PM	#2
CTScott ULTIMATE View User's Garage Drives: 09 5dr LB, 2x 08 3dr LB Join Date: Oct 2008 Location: USA, CT Posts: 13,460	It can be: -Fuel cap (loose) - Leakage from EVAP line (Canister - Fuel tank) - Leakage from EVAP line (Purge VSV - Canister) - Canister pump module - Leakage from fuel tank - Leakage from canister Is this happening on your 2010? __________________

10-20-2011, 06:17 PM	#3
yaris2010RS View User's Garage Drives: no-longer-boosted '10 Yaris Join Date: Nov 2009 Location: Angus, Ontario Posts: 1,891	yep its on my 2010..... i want to take it to the dealership but not sure if it could have been caused by any of my mods (header) this weekend i will remove header and intake and take it in if i cant find the issue __________________ If it has boobs or wheels sooner or later your gonna have problems with it

10-20-2011, 07:33 PM	#4
CTScott ULTIMATE View User's Garage Drives: 09 5dr LB, 2x 08 3dr LB Join Date: Oct 2008 Location: USA, CT Posts: 13,460	Not the header, but check the vacuum purge valve hoses that are by the intake. __________________

10-20-2011, 08:25 PM	#5
yaris2010RS View User's Garage Drives: no-longer-boosted '10 Yaris Join Date: Nov 2009 Location: Angus, Ontario Posts: 1,891	by the intake or on the intake? (run near it on connected to it?) could water be the issue here? maybe on purge valve? __________________ If it has boobs or wheels sooner or later your gonna have problems with it

10-20-2011, 09:10 PM	#8
CTScott ULTIMATE View User's Garage Drives: 09 5dr LB, 2x 08 3dr LB Join Date: Oct 2008 Location: USA, CT Posts: 13,460	It gets measured 5 hours after the vehicle is powered off. A kink wouldn't do it, it has to be a leak. Leak detection pump creates negative pressure (vacuum) in EVAP system and EVAP system pressure measured. Reference pressure measured at start and at end of leak check. If stabilized pressure higher than second reference pressure, ECM determines that EVAP system has small leak. __________________

10-20-2011, 09:19 PM	#9
yaris2010RS View User's Garage Drives: no-longer-boosted '10 Yaris Join Date: Nov 2009 Location: Angus, Ontario Posts: 1,891	lol so its not as easy as turning the car on and feeling for a leak. lol it consideres it a small leak so ill never find it. look like header and intake are coming out and its going into the dealer ship __________________ If it has boobs or wheels sooner or later your gonna have problems with it

10-20-2011, 09:40 PM	#12
CTScott ULTIMATE View User's Garage Drives: 09 5dr LB, 2x 08 3dr LB Join Date: Oct 2008 Location: USA, CT Posts: 13,460	It is T-EG048-07, but it is not for DTC P0456, it is for DTCs P043E, P043F, P2401, P2402, and P2419. __________________

10-20-2011, 09:50 PM	#13
yaris2010RS View User's Garage Drives: no-longer-boosted '10 Yaris Join Date: Nov 2009 Location: Angus, Ontario Posts: 1,891	HA! and i dont have those so its off to the dealer i go :p. only thing is ill need to wait till i get a chance to take intake and header out. so the computer only scans the evap system 5 hours after the car has been turned off? so as long as i resist the urge to go out tonight in the morning the system would have been tested? (i can confirm this after with my scan tool and it displaying a run in relation to the evap) and if its not on in the morning that means i have a intermittent leak? __________________ If it has boobs or wheels sooner or later your gonna have problems with it

10-20-2011, 09:55 PM	#14
CTScott ULTIMATE View User's Garage Drives: 09 5dr LB, 2x 08 3dr LB Join Date: Oct 2008 Location: USA, CT Posts: 13,460	Correct. __________________

10-20-2011, 09:59 PM	#15
yaris2010RS View User's Garage Drives: no-longer-boosted '10 Yaris Join Date: Nov 2009 Location: Angus, Ontario Posts: 1,891	OMG THATS SO GONNA SUCK!!!! i really hope to god its either on in the morning or never on again....... thanks CTScott for all your help __________________ If it has boobs or wheels sooner or later your gonna have problems with it

10-21-2011, 08:13 AM	#16
yaris2010RS View User's Garage Drives: no-longer-boosted '10 Yaris Join Date: Nov 2009 Location: Angus, Ontario Posts: 1,891	so this morning the engine light was not on. i ran the scan tool anyways and found the car had not run the evp system check over night(probably due to the c02 check not being preformed while i was drived the night before) im now at school and its another +5 hours till i go out to my car so i will see then if the check was run and if it passed or not. just thought id give a quick update __________________ If it has boobs or wheels sooner or later your gonna have problems with it

10-24-2011, 11:13 AM	#17
yaris2010RS View User's Garage Drives: no-longer-boosted '10 Yaris Join Date: Nov 2009 Location: Angus, Ontario Posts: 1,891	since no one ever does this, ill update this. ***issue seems to have been resolved, anyone with a after market intake should check for this*** 000.jpg apparently the Ziptie i had used to hold the purgevalve in place failed and the entire thing fell to where my shifter linkages were and when it got hit it cracked. this part is 139.99 from the dealership (i got one free off a wrecked corolla which is a different part # and looks different but it seems to be working.) when i get home from school today i will post picks of the old valve and hopefully tonight the computer will run the evap test and throw no codes fingers crossed __________________ If it has boobs or wheels sooner or later your gonna have problems with it

12-04-2012, 10:50 AM	#18
jemmah Drives: Toyota Yaris Join Date: May 2009 Location: Cape Cod MA. USA Posts: 14	I've got a 2007 Yaris with 200k miles. I've had a p0456 code twice over the years. Both times I OVER filled the fuel tank. Both times the code would show up the next morning. If you over-filled this could be the problem. Please check this situation first before you start tearing everything apart!! I assume there was fuel flow into the charcoal canster and the by-pass opened.

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