I have a 2004 Yukon XL GMC and I'm getting code

These codes let you know the engine is running to lean on gasoline . May be only a plugged fuel filter or weak fuel pump. A vacuum leak can cause this problem . The engine controller may need reprograming with new software. Dirty fuel injectors. Try adding fuel conditioner to the gas tank and changing fuel filter.

Hi there:
The DTC P0449 fault code is one of two things 90 percent of the time... either your gas cap is not sealing or your evap vent solenoid is not sealing either.


The code means you have a large evap leak. The evap solenoid is locate near or beside it and has a electrical connector that goes to it. It is either round or square



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engine lights came on and the codes are po449 and po449p on a 2007 chevy avalanche

Could be the HVAC control processor is malfunctioning.Wtihout testing that would just be a guess .
2003 Tahoe No Rear Heat Fix Suburban Yukon XL Repair

Could be more, tune up, fuel filter, vacuum leak.

{: ) It's either you shoud have the Radio VIN releaarned by a scan tool, or you may need to reprogram the radio using GM's SPS programming.

ac on a 2005 gmc yukon not blowing and cant here compressor the rear ac of the truck is working fine, are there any fuses i can check?

Code po449 is the canister vent valve solenoid error.This is a common problem with these valves because they are under the truck in the rear by the spare tire and they get all the dirt and water and snow,if you live in an area where you get snow.You will find it on the canister under the vehicle by the spare tire.

Dealer can give you the code,call them with your vin number.

disconnect ur positive battery cable. make sure not to set alarm with remote. let set for about 5 minutes, this happened to my 2003 gmc yukon xl and it actually worked