Lnf p0449
05-31-2017, 11:46 AM
#1
Lnf p0449
So my sedan sat for two days then I got in it and started it yesterday morning and had a CEL. I am getting a P0449. I filled up gas on Sunday morning before I parked it. I checked the EVAP purged valve on the intake manifold and it is good. It only has 10k miles but I still checked it. I also checked the wiring under the rear of the car and it is fine.
So before I just start replacing things I am wondering. I know it can be a few different things such as:
-gas cap
-canister vent valve solenoid
-vapor canister
If I clear the CEL it comes back right after I turn the car off then on. This makes me think it is something electronic. I pulled the vent valve solenoid on the vapor canister and it appeared to be fine. Also over the past few months I noticed my MPG has been only 27MPG and I usually get 30MPG (both mixed of around town and highway). I know the gas cap and vent valve solenoid are relatively cheap but I would like to see if anyone else has had this problem.
So before I just start replacing things I am wondering. I know it can be a few different things such as:
-gas cap
-canister vent valve solenoid
-vapor canister
If I clear the CEL it comes back right after I turn the car off then on. This makes me think it is something electronic. I pulled the vent valve solenoid on the vapor canister and it appeared to be fine. Also over the past few months I noticed my MPG has been only 27MPG and I usually get 30MPG (both mixed of around town and highway). I know the gas cap and vent valve solenoid are relatively cheap but I would like to see if anyone else has had this problem.
05-31-2017, 02:40 PM
#2
Senior Member
I haven't had the issue on the Balt, but over the years as a mechanic I've seen GM vent solenoids fail left and right. Did you just inspect it, or did you try to actuate it with power?
If you didn't, take it off and use some jumper wires and tap it to the battery and see if it gives a satisfying thunk.
Edit: Forgot to add, if you have access to a scan tool(Snap-on, OTC, etc.) you can actuate it via the pcm and see if you have a good power and ground at the connector.
If you didn't, take it off and use some jumper wires and tap it to the battery and see if it gives a satisfying thunk.
Edit: Forgot to add, if you have access to a scan tool(Snap-on, OTC, etc.) you can actuate it via the pcm and see if you have a good power and ground at the connector.
05-31-2017, 03:17 PM
#3
I haven't had the issue on the Balt, but over the years as a mechanic I've seen GM vent solenoids fail left and right. Did you just inspect it, or did you try to actuate it with power?
If you didn't, take it off and use some jumper wires and tap it to the battery and see if it gives a satisfying thunk.
Edit: Forgot to add, if you have access to a scan tool(Snap-on, OTC, etc.) you can actuate it via the pcm and see if you have a good power and ground at the connector.
If you didn't, take it off and use some jumper wires and tap it to the battery and see if it gives a satisfying thunk.
Edit: Forgot to add, if you have access to a scan tool(Snap-on, OTC, etc.) you can actuate it via the pcm and see if you have a good power and ground at the connector.
02-15-2018, 09:09 AM
#4
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Join Date: 01-26-11
Location: Manassas, VA
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Did you figure out what the culprit was? My HHR SS just popped the same code after sitting like you said, I cleared the code and it came back after a short ride.
02-28-2018, 11:37 AM
#17
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So I had a buddy with a scanner run the code and it was the vent solenoid, the purge was clicking and functioning as it should when we tested it. So I replaced the vent solenoid this past weekend and have driven over 3 full drive cycles and it's not going away. Could it be something else other than the vent solenoid?
