code PO496

[kingsfisherman]

Hello All,

 

code PO496

 

Would like to know more about this code, 

can it cause fumes in the cab?

it does cause rough start after re fueling.

any other problems to know of?

[Supreme Pizza]

Everything you ever wanted to know about that code: 

 

 https://www.obd-codes.com/p0496

[swathdiver]

From the shop manual:

 

DTC P0496
Evaporative Emission System Flow During Non-Purge
CIRCUIT/SYSTEM DESCRIPTION
This DTC tests for undesired intake manifold vacuum flow to the evaporative emission (EVAP) system. The
engine control module (ECM) seals the EVAP system by commanding the EVAP canister purge solenoid valve
OFF and the EVAP canister vent solenoid valve ON. The ECM 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.

 

CONDITIONS FOR RUNNING THE DTC

 The ignition voltage is between 11-18 volts.
 The barometric pressure (BARO) is more than 74 kPa.
 The fuel level is between 15-85 percent.
 The engine coolant temperature (ECT) is less than 35°C (95°F).
 The intake air temperature (IAT) is between 4-30°C (39-86°F).
 DTC P0496 runs once per cold start when the above conditions are met.

 

CONDITIONS FOR SETTING THE DTC

 

The ECM detects more than 10 inch H2O vacuum for 5 seconds during a non-purge condition.

CIRCUIT/SYSTEM TESTING

 

1. Start the engine.
2. Seal the EVAP system using the Purge/Seal function with a scan tool.
3. Observe the FTP sensor with a scan tool. The Fuel Tank Pressure Sensor parameter should be less than
1.7 volts after 90 seconds.
 If the Fuel Tank Pressure Sensor parameter is greater than the specified range, replace the EVAP
canister purge solenoid valve.

[carnau]

14 hours ago, kingsfisherman said:

Hello All,

 

code PO496

 

Would like to know more about this code, 

can it cause fumes in the cab?

it does cause rough start after re fueling.

any other problems to know of?

Yes. It will definitely caused rough start after refueling. My truck has had this code in the past and when I would get gas I would just leave my truck running (which they say is a big No No) and I wouldn't have any problems with it after lol.

I have not run into any problems with fumes on the inside of the cab because if it because it just dumps directly into the intake. I believe I made a video of replacing one on a truck like yours. I just can't remember if yours is on the side of the manifold or the top.

[carnau]

Here is the video I did. If yours is on the side of the manifold you just don't have to remove a bolt. It is a cheap fix.

 

 

[carnau]

After doing some more research on a 2009 Silverado, Yes yours is on the side. Still an easy fix and inexpensive. $20 To repair.
Here is the part you need. https://amzn.to/2BEOupT
 

Here is the location. Hope this helps.