code p0496 - LS1GTO.com Forums

Vendors


Go Back   LS1GTO.com Forums > GTO Tech > LS1/LS2 Engine Tech

Reply
 
Thread Tools Rate Thread
Old 09-16-2007, 08:04 PM   #1
bearsfaninwisc
Registered User
 
bearsfaninwisc's Avatar
 
2005 GTO Owner

Join Date: May 2007
Location: wisconsin dells,WI
Posts: 120


Offline
code p0496

Hey all,need some advice,I filled up with gas yesterday and made a 200 mile road trip.Woke up today and the gas tank was at half full and went for a spin and 30 seconds into my drive I gave it a little and noticed that the engine seemed to bog a than it shifted down into first and went and then noticed the ses light was on????

Could this code just be the gas cap?If so why would it bog from a loose gas cap?I would like to also add that the woman had it yesterday and filled it up with 87 gas....Thanx for any help!
__________________

05 gto stock
00 bonneville ssei
97 gran prix gt
  Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Old 09-16-2007, 08:07 PM   #2
gotzaGTO
CAUTION!!!!
 
gotzaGTO's Avatar
 
2004 GTO Owner

Join Date: Sep 2004
Location: ehhh...who cares.
Posts: 9,886


Offline
P0496 Evaporative Emission Sys High Purge Flow
__________________
  Reply With Quote Quick reply to this message
Old 09-16-2007, 08:15 PM   #3
bearsfaninwisc
Registered User
 
bearsfaninwisc's Avatar
 
2005 GTO Owner

Join Date: May 2007
Location: wisconsin dells,WI
Posts: 120


Offline
Thanx but I know what the code stands for but what causes it???
  Reply With Quote Quick reply to this message
Old 09-16-2007, 09:19 PM   #4
Gonna_Try_One
Registered User
 
Gonna_Try_One's Avatar
 
2004 GTO Owner

Join Date: Dec 2004
Location: Prairieville, LA
Posts: 1,683


Offline
Quote:
Originally Posted by bearsfaninwisc...View Post
Thanx but I know what the code stands for but what causes it???

Not the cap.

When the check for that code is run, the purge solenoid is commanded off (closed), and the vent solenoid is commanded closed. Fuel level has to be between 15-85%. Ran during cold start-up (ECT between 39-86* F).

If this code sets, it means the fuel tank pressure sensor has detected vacumn in the tank when there shouldn't be any. This means either the purge solenoid is leaking when closed, or the tank pressure sensor itself is at fault and giving a false reading to the PCM.
__________________
2004 Quicksilver M6 -pieces all over the South
Current Ride = 2009 1500 Silverado Z71, Procharger P-1SC-1 (8 psi), 3 core intercooler, AFE catback, HD hood, SLP bumper cover, color matched grill, Spyder projector headlights, LED taillights, HID low beams and fog lights
2012 Camaro 2SS/RS LS3/M6, Hurst shifter, Rotofab CAI, Corsa Sport exhaust, factory (convertible) strut brace
  Reply With Quote Quick reply to this message
Old 09-16-2007, 10:49 PM   #5
bearsfaninwisc
Registered User
 
bearsfaninwisc's Avatar
 
2005 GTO Owner

Join Date: May 2007
Location: wisconsin dells,WI
Posts: 120


Offline
Thank you very much,looks like I will be making a trip to the stealership tomarrow seeing as,get this I have only 122 miles left on my bumper to bumber warranty.What a break for me I guess.
  Reply With Quote Quick reply to this message
Old 09-16-2007, 11:05 PM   #6
bearsfaninwisc
Registered User
 
bearsfaninwisc's Avatar
 
2005 GTO Owner

Join Date: May 2007
Location: wisconsin dells,WI
Posts: 120


Offline
I have read at other forums that code p0496 is usually caused by a fualty or dirty purge valve and it is a inexpensive part to replace like $20 or so.Where on our caars is the purge valve located at so I can just do it myself seeing as who knows when the stealership will be able to get to my car?Thanx for any info!
  Reply With Quote Quick reply to this message
Old 09-17-2007, 07:15 AM   #7
Gonna_Try_One
Registered User
 
Gonna_Try_One's Avatar
 
2004 GTO Owner

Join Date: Dec 2004
Location: Prairieville, LA
Posts: 1,683


Offline
Quote:
Originally Posted by bearsfaninwisc...View Post
I have read at other forums that code p0496 is usually caused by a fualty or dirty purge valve and it is a inexpensive part to replace like $20 or so.Where on our caars is the purge valve located at so I can just do it myself seeing as who knows when the stealership will be able to get to my car?Thanx for any info!

I almost typed in where it is on an '04'. On the '05', it is the valve right in front of the oil fill, mounted to the front of the right head.
  Reply With Quote Quick reply to this message
Old 09-17-2007, 10:59 AM   #8
Ozzhead
Registered User
 
Ozzhead's Avatar
 
2006 GTO Owner

Join Date: May 2006
Location: Livermore, CA
Posts: 249


Offline
Here is what my GMsi says to do,

DTC P0496
System Description

This DTC tests for undesired intake manifold vacuum flow to the Evaporative Emission (EVAP) System. The control module seals the EVAP System by commanding the EVAP canister purge solenoid valve Closed and the EVAP canister vent solenoid valve Closed. The control module monitors the fuel tank pressure (FTP) sensor to determine if a vacuum is being drawn on the EVAP System. If vacuum in the EVAP system is more than a predetermined value within a predetermined time, this DTC sets.

The following table illustrates the relationship between the ON and OFF states, and the Open or Closed states of the EVAP canister purge and vent solenoid valves.

Control Module Command


EVAP Canister Purge Solenoid Valve


EVAP Canister Vent Solenoid Valve

ON


Open


Closed

OFF


Closed


Open
DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0496 Evaporative Emission (EVAP) System Flow During Non-Purge
Conditions for Running the DTC

* DTCs P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0222, P0223, P0442, P0443, P0449, P0451, P0452, P0453, P0454, P0464, P0496, P0608, P2101, P2119, P2120, P2122, P2123, P2125, P2127, P2128, P2135, P2138 are not set.
* The ignition voltage is between 10-18 volts.
* The barometric pressure (BARO) is more than 75 kPa.
* The fuel level is between 15-85 percent.
* The engine coolant temperature (ECT) is between 4-30C (39-86F).
* The intake air temperature (IAT) is between 4-30C (39-86F).
* The start up ECT and IAT are within 9C (16F) of each other.
* The vehicle speed sensor (VSS) is less than 121 km/h (75 mph).
* DTC P0496 runs once per cold start when the above conditions are met.

Conditions for Setting the DTC

The control module detects vacuum during a non-purge condition.
Action Taken When the DTC Sets

* The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
* The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

Conditions for Clearing the MIL/DTC

* The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
* A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
* A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
* Clear the MIL and the DTC with a scan tool.

Step


Action


Values


Yes


No

Schematic Reference: Evaporative Emissions (EVAP) Hose Routing Diagram

1


Did you perform the Diagnostic System Check - Vehicle?


--


Go to Step 2


Go to Diagnostic System Check - Vehicle

2


1. Start the engine.
2. Seal the Evaporative Emission (EVAP) System using the Purge/Seal function with a scan tool.
3. Increase the engine idle to 1,200-1,500 RPM.
4. Observe the fuel tank pressure (FTP) sensor in H2O with a scan tool.

Is the fuel tank pressure sensor parameter within the specified value?


-1 to +1 H2O


Go to Diagnostic Aids


Go to Step 3

3


1. Turn OFF the ignition.
2. Disconnect the EVAP purge pipe from the EVAP canister purge solenoid valve.
3. Turn ON the ignition, with the engine OFF.
4. Observe the FTP sensor in H2O with a scan tool.

Is the fuel tank pressure sensor parameter within the specified range?


-1 to +1 H2O


Go to Step 4


Go to Step 5

4


Replace the EVAP canister purge solenoid valve. Refer to Evaporative Emission (EVAP) Canister Purge Solenoid Valve Replacement .

Did you complete the replacement?


--


Go to Step 6


--

5


Replace the FTP sensor. Refer to Fuel Tank Pressure Sensor Replacement .

Did you complete the replacement?


--


Go to Step 6


--

6


1. Connect all EVAP hardware that was previously disconnected.
2. Seal the EVAP System using the Purge/Seal function with a scan tool.
3. Start the engine and idle at 1,200-1,500 RPM.
4. Observe the fuel tank pressure sensor parameter with a scan tool.

Is the fuel tank pressure sensor parameter within the specified range?


-1 to +1 H2O


Go to Step 7


Go to Step 2

7


Observe the Capture Info with a scan tool.

Have any DTCs not been diagnosed?


--


Go to Diagnostic Trouble Code (DTC) List - Vehicle


System OK
  Reply With Quote Quick reply to this message
Old 09-17-2007, 05:06 PM   #9
bearsfaninwisc
Registered User
 
bearsfaninwisc's Avatar
 
2005 GTO Owner

Join Date: May 2007
Location: wisconsin dells,WI
Posts: 120


Offline
Thanx for all your help.I found it just like you described and will be doing it tomarrow.Part costed me $21.75.
  Reply With Quote Quick reply to this message
Old 03-17-2009, 01:07 AM   #10
Gtogoat06
Custom Goat 06 Riding Dirty
 
Gtogoat06's Avatar
 
2006 GTO Owner

Join Date: Nov 2006
Location: Saint Louis, MO
Posts: 472


Offline
Send a message via AIM to Gtogoat06 Send a message via MSN to Gtogoat06
yea i just flagged this damn code will be dropping her off to the dealership tomorrow it is a cheap part buyt dealership is like 4 miles away and they can fix it under my warranty penny pinching gets me my mods lol
  Reply With Quote Quick reply to this message
Old 03-17-2009, 04:35 AM   #11
Junkyard Dog
Registered User
 
Junkyard Dog's Avatar
 
2004 GTO Owner

Join Date: Jan 2008
Location: Coventry, RI
Posts: 526


Offline
Send a message via AIM to Junkyard Dog
I have the exact issue with my 04 Avalanche which is out of warranty I'm just going to replace both valves at under $75.00 and less than a trip to the dealer.
__________________
  Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the LS1GTO.com Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -8. The time now is 02:51 AM.




Powered by vBulletin® Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright 2003-2008, LS1GTO.com
Site Banner Design 2005-2007, Cylosoft

LS1GTO.com is not affiliated with General Motors Corp.