GMC / Chevy Truck -DTC P0449 EVAP Vent Solenoid Control Circuit

Come along with Eric O at the SMA shope as he diagnoses and repairs this GMC Sierra that came in with a check engine light on and a DTC P0449 “Evaporative Emission (EVAP) Vent Solenoid Control Circuit” Now this is a really common problem that plagues these Chevrolet and GMC pick ups and is an easy one to figure out! Thanks for watching!

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  1. Eric that vent S.C.circuit why can't they completely seal them and save the driver's money good call on that by the way keep up the good work look forward to the next one.

  2. Really enjoy watching your videos on my second monitor on days I'm in the office. I'm pretty amazed at how much rust the cars up north have though…My car is 2 or 3 times older than the cars you work on and it hardly has any rust in the bottom.

  3. this is a common issue on these trucks … the get filled with dirt/mud ( as you can see from the dirt on the truck ) there is an updated part by GM where you reroute the pre filter to a new location and use heater hose for the hose and use ban clamps to connect everything…

    you can also use a noid light in the connector and use it to test the circuit. the gm one in the kit fits perfectly in most connectors. typically use to test injector pulses

    i work as a drive ability tech for GMC dealership

  4. Hey there Eric….1st I wanna thank you for taking the time to make these videos,2nd really enjoy your sense of humor…man you crack me up sometimes!..Both my daughters drive Chevy Cruzes and one of the cars has codes of the following..PO171,PO2270. So performed a smoke vacuum test and seen smoke coming from a pin hole near the bottom of the brake fluid reservoir(very weird)..then after smoke test codes UO100 and UO140…..your thoughts

  5. Question. You obviously have some type of service that gives you the "Flat Rate Time" for doing repairs. Back in the "Dark Ages" we had a Mitchell or Chilton book that listed the times for various services. What do you use now? I've noticed you use a couple of different devices when diagnosing an issue. Do you use different "Pads" for different problems? Thanks. OH. The "Dark Ages" was before the "WWW" hit.

  6. In technical school we have been taught to never use a test light on a computerized circuit because it draws to much amperage? Can you explain this Eric? Because I see in a lot of your videos the Test Light is your best friend 🙂

  7. The problem with the vent valves is they get dirt in them and they stick. Or they fail electrically. A lot of the time it's from dust ingestion a least here in the south. They get dirt in them because the air intake for the vent valve is on the fuel filler neck or they have been moved up on top of the trans as per GM's bulletin. But the still get dirt/dust in them. So why not hook the EVAP intake hose to the filtered air side of the air cleaner? Which would prevent dirt/dust ingestion.

  8. Just had this same issue on a 03 pontiac aztek. went thru all wiring couldn't find a diagram for the wiring. found a bare wire on my cruise control module harness. fixed it, reset codes, problem solved. so assuming evap runs thru it. never knew

  9. I do testing and build the testing equipment for the dust testing ingestion on this very same cyclonic/ CVS. It is tested to GMW-15826 and ISO-5011. These are very complex testing specifications. I'm surprised of the failure noted in this. The prefilter is in the upper intake by the filler neck , the cyclonic filter has a capacity of 40 gram , tested with ISO- fine dust. After the dust exposure it is tested to leak < 9 cc/minuet. There may be an issue of salt fog being sucked into the valve and make it freeze up. Not a failure mode in the test lab. Great video!
    I wonder if you have put 12vdc to the terminals to see if it activates the solenoid after removal? Almost needs a bore scope to look inside the ports to see dust cake build up, or anything else.

  10. I WISH mine looked like that – I have a 2002 GMC Sierra 1500 and NO way can I get to it. It appears on mine it is ABOVE the tank, above a frame rail with zero accessibility – I mean short of dropping the tank, I have no clue how to reach it ….am I missing something ? Nothing at the rear of the tank. I go to the front (toward the engine) and I can just make out what looks like that ribbed clip that holds it in place (if this is even the right thing). There is what looks like a ground wire to a bolt and a free hose venting to AIR …Hoping you tell me "That's not it to xyz" cause this is not a do it yourself on this model

  11. Jerk Chevy dealers selling all components separately… Vent Valve and lines… DIYer’s please take note!! Tried to get one over on me but I was able to get the lines off… (submerge in boiling water) Vent control valve comes just like the one pictured in his video!!!

  12. Hey Eric, when you get this code, can you also get the P0455 code along with it?
    I have an 08 GMC Sierra that started with P0455(large leak) now im getting P0449
    Thank you

  13. Well now I'm totally confused because there's an evap vent control solenoid under the hood at the front of the intake and another evep purge valve under the truck just ahead of the gas tank > I'm replacing the one under the hood because my code was a P0455 and that's what is recommended .

  14. Four years I was asked to look at a Saturn vue. It had a po449 code. Well I hooked up my 194 bulb test light and used my modis to buy directionally control it. Well the light didn't light so upon further inspection in the wire loom I found a corroded broken wire. Fixed the wire reconnected the connector to the vent solenoid and tried my test again. This time it clicked. Got paid and shipped it. Owner calls me two hours later and informs me he has had this problem for over a year and it's been looked at by two other shops. I said I am sorry. He had about given up.. simple broken wire and he showed my the list of parts that were thrown at this car

  15. Another thing i do is go buy a 10.00 spray jug at walley world.
    Buy a gallon of trans fluid along with a quart bottle of alcohol, mix together,and go to town every year under from cab back.
    It spreads like you wont believe.
    Every time i go to get my yearly inspection my guy wants to buy my truck. Says it looks new underneath.Smells bad for a few days but i can live with it.
    115,000 miles.

  16. Did this truck have issues with trying to fill the gas tank? Ive got an 07 Pontiac Grand Prix with the 5.3 V8 and I am lead to believe that the problem is this exact issue with the vent solenoid. I've got a check engine light with a p0446 code that comes up and at the gas pump, it won't let me pump at full speed and will automatically kick it off (it does this mostly in the winter time when it's cold) Any input helps. Thanks.

  17. Good video with accurate information. I would of used a volt meter however the snapon test light with bannana clips is great. Please make more videos. There are to many amateur videos with incorrect Diagnostics methods/ procedures and incorrect information on YouTube.

  18. great vid, is there a way to actuate these solenoids without the expensive scan tool? maybe with a no screen model scan tool or a laptop + odb2 adaptor w/certain software or some other method?

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