P0449 Code Help
#11
First, congrats on fixing your issue.
I was correcting your oversimplification not to belabor this OLD thread, but for the benefit of others that may stumble across it while in a search.
P0449
Possible causes
- Vacuum leaks, damaged hoses or improper routing
- EVAP system - Check fuel cap, canister, valves or components
- Faulty purge or vent solenoids
- Check connector and wiring
- Fuel saturated vapor canister
- Failed EVAP vent solenoid
It happens often that a leak upstream from the solenoid tricks the PCM into thinking there is a fault with the solenoid itself. Then, those that believe "follow what the all powerful computer tells you" get to fixin what ain't broke.
My point, OBD codes are great, but you still have to use your brain.
I was correcting your oversimplification not to belabor this OLD thread, but for the benefit of others that may stumble across it while in a search.
P0449
Possible causes
- Vacuum leaks, damaged hoses or improper routing
- EVAP system - Check fuel cap, canister, valves or components
- Faulty purge or vent solenoids
- Check connector and wiring
- Fuel saturated vapor canister
- Failed EVAP vent solenoid
It happens often that a leak upstream from the solenoid tricks the PCM into thinking there is a fault with the solenoid itself. Then, those that believe "follow what the all powerful computer tells you" get to fixin what ain't broke.
My point, OBD codes are great, but you still have to use your brain.
#12
Since this thread has been shocked back to life again..
Just an FYI- A new AC Delco vent valve solenoid can be bought without the hose for about 20 bucks on fleabay. The part number including the hose is costing you another $100 +. If you are careful you can remove the hose and re-use it on the new assembly.
I simply cut off about an inch at the flange where the hose was distorted from the fitting, then heated that cut end of the hose in hot water and slipped in onto the new solenoid. My assembly was cracked and leaking. 20 bucks and no more code.
The plastic of the factory solenoid body is known to swell and crack over time. Easy to inspect and check for leaks visually
Just an FYI- A new AC Delco vent valve solenoid can be bought without the hose for about 20 bucks on fleabay. The part number including the hose is costing you another $100 +. If you are careful you can remove the hose and re-use it on the new assembly.
I simply cut off about an inch at the flange where the hose was distorted from the fitting, then heated that cut end of the hose in hot water and slipped in onto the new solenoid. My assembly was cracked and leaking. 20 bucks and no more code.
The plastic of the factory solenoid body is known to swell and crack over time. Easy to inspect and check for leaks visually
Last edited by Xlr8n; 02-06-2014 at 02:46 PM.
#13
yes, vent valve, had to replace mine, code NEVER came back. Cheap and easy repair:
https://www.hummerforums.com/forum/h...control-30289/
https://www.hummerforums.com/forum/h...control-30289/
Last edited by hummerz; 02-06-2014 at 05:05 PM.
#14
Hello,
I am also dealing with the P0449 code...Please keep in mind that this code is a circuit/wiring problem and not a leak issue...the part that is related to this code is the VENT solenoid which is located in the back by gas tank.Do not get it confused with the purge valve which is located behind alternator which u have to remove the driver side tire and wheel well cover to r&r....if your code was a small or large leak it can also be the vent solenoid which would be cracked that you could easily see... you could try and shotgun the vent solenoid at it to see if that fixes the problem roughly 142.00 smackers... with my h3 the pending code will appear on the reader when it is wet out... so I am going to look at the connector to the vent solenoid and check for any chaffing and check the connector itself...I believe that moisture is getting inside the connector and giving me my problem... I will be cleaning the connector applying electrical insulating compound, spraying all wires with silicone release fluid and finally shrink wrapping all wires and plug....I will keep you posted as to the outcome
I am also dealing with the P0449 code...Please keep in mind that this code is a circuit/wiring problem and not a leak issue...the part that is related to this code is the VENT solenoid which is located in the back by gas tank.Do not get it confused with the purge valve which is located behind alternator which u have to remove the driver side tire and wheel well cover to r&r....if your code was a small or large leak it can also be the vent solenoid which would be cracked that you could easily see... you could try and shotgun the vent solenoid at it to see if that fixes the problem roughly 142.00 smackers... with my h3 the pending code will appear on the reader when it is wet out... so I am going to look at the connector to the vent solenoid and check for any chaffing and check the connector itself...I believe that moisture is getting inside the connector and giving me my problem... I will be cleaning the connector applying electrical insulating compound, spraying all wires with silicone release fluid and finally shrink wrapping all wires and plug....I will keep you posted as to the outcome
#15
Vid on how the evap system operates:
Last edited by hummerz; 02-06-2014 at 05:49 PM.
#16
OBD-II Check Engine Light Trouble Codes
scroll down to code p0449, and when you get time, look at how many codes are listed for the evap system.
Last edited by hummerz; 02-06-2014 at 06:38 PM.
#17
I had this same problem and purchased the EVAP solenoid and wiring through GM Parts Center | Discount Prices on GM Parts and Free Shipping for $132 and problem was fixed. The code disappeared and I didn't have any more problems pumping gas.
#18
I had this same problem and purchased the EVAP solenoid and wiring through GM Parts Center | Discount Prices on GM Parts and Free Shipping for $132 and problem was fixed. The code disappeared and I didn't have any more problems pumping gas.
#19
P0449
Possible causes
- Vacuum leaks, damaged hoses or improper routing
- EVAP system - Check fuel cap, canister, valves or components
- Faulty purge or vent solenoids
- Check connector and wiring
- Fuel saturated vapor canister
- Failed EVAP vent solenoid
It happens often that a leak upstream from the solenoid tricks the PCM into thinking there is a fault with the solenoid itself. Then, those that believe "follow what the all powerful computer tells you" get to fixin what ain't broke.
My point, OBD codes are great, but you still have to use your brain.
Possible causes
- Vacuum leaks, damaged hoses or improper routing
- EVAP system - Check fuel cap, canister, valves or components
- Faulty purge or vent solenoids
- Check connector and wiring
- Fuel saturated vapor canister
- Failed EVAP vent solenoid
It happens often that a leak upstream from the solenoid tricks the PCM into thinking there is a fault with the solenoid itself. Then, those that believe "follow what the all powerful computer tells you" get to fixin what ain't broke.
My point, OBD codes are great, but you still have to use your brain.
Sometimes you have to hook up a smoke machine if the vent valve,purge,etc all check out...I've seen fuel pumps rusted, rotted gas tanks....
GM veichles do not like aftermarket gas caps...if your veichle needs a gas cap put a OEM in.
#20
That would send another code for evap leak, p0442, p0455 (most common) p0456, etc.. All for evap leaks.. I have never found an evap leak when only retrieving a p0449, from the computer! Scan the computer and it will give you all the codes, if you receive an evap leak code along with the p0449, then you should be looking for a leak, otherwise, if you only receive the p0449, replace the vent valve.