catdaddy137

when i cranked my car this am the check engine light came on....it seems to be running fine....i got the parts store to check the code....i drove it on my route , 265 miles , and the mpg did not change , meaning it got no worse or better....it is 08 2lt 2.4 auto with about 112,000 miles...and no mods to the intake yet..... the code is PO496 EVAP EMISSION HIGH , PURGE FLOW FAULT.........any help or suggestions are welcome , as i prefer to do my own mechanic work......thanks.

ChevyMgr

Purge valve/solenoid.

ChevyMgr

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. The preceding 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.

Conditions for Setting the DTC
• The ECM detects vacuum during a non-purge condition.

• The fuel tank vacuum is greater than 4 inches H2O or less than -4 in H2O for 5 seconds within 10 minutes of cold start.

• The 10 minute test must be completed before this DTC will set.



Evaporative Emission Canister Purge Solenoid Valve Replacement
Removal Procedure




1 Remove the air cleaner assembly from the studs and reposition to the side.
2 Disconnect the evaporative emission (EVAP) canister purge valve electrical connector (1).



3 Disconnect the EVAP canister purge valve tube from the intake manifold. Refer to Plastic Collar Quick Connect Fitting Service .
4 Disconnect the chassis EVAP vapor line from the EVAP canister purge valve. Refer to Plastic Collar Quick Connect Fitting Service .



5 Remove the EVAP canister purge valve bracket bolt.
6 Remove the EVAP canister purge valve with bracket.
7 Remove the EVAP canister purge valve from the bracket.
8 Inspect for carbon release in the EVAP canister purge valve ports. If there is any loose carbon, replace the EVAP canister and any components necessary to remove the carbon particles.
Installation Procedure

catdaddy137

thanks so much for that great info...i decided , with suggestion from a mechanic , that i'm just going to reset it and wait to see if it comes back , before doing any testing/replacing.

catdaddy137

i did replace the purge valve...it was the problem.....no problems with the engine since...i think it helped with my mpg also.....thanks for the great help.

kddonelson

Funny you should mention that you thought you mileage got better. I was replacing the gaskets in my 2006 2.4 oil cooler (argh) and while upside-down under hood getting to the two bottom bolts of the cooler I put too much pressure on the purge valve and broke the input vacuum line off. After finishing with the oil cooler I decided to just glue the plastic nipple back on the purge valve so I could run the car to check for oil leaks.

Nipple glued, all back together, started engine and heard a slight but distinct vacuum leak. I knew that I hadn't totally sealed the broken nipple into the purge valve. Not being too worried about it, since I had an idea what it was, I drove it that way for a week before the check engine light came on. I thought - "ok, time to fix that thing I broke while fixing that other thing" (the story of my life).

The interesting part of this tale is that during the week I drove my HHR with the leaky purge valve I got better gas mileage by 1.5 - 2 mpg. I was thinking about leaving it that way until the CEL came on. I'd run it that way longer if it wasn't for the fact that the valve is less than $20 and I need to get a state vehicle safety inspection at the end of this month. They won't pass it with any CEL codes on in Texas.

I love my 2006 HHR 2.4! Quirky as it is. Thanks to the awesome contributors to this site.

donbrew

4 years ago. At least it refreshes the info to the top.