P0449-How To Replace Evap. Vent Solenoid

[Bigredmariner]

I have no schematic, but if you watch that video that I just added to the OP it may help you to use a test light on the connectors.

Also, did you reset the code and it came back? Or did it just never clear?

If you didn't clear it, it will take several drive cycles to clear on it's own. You can clear it by removing the negative of the battery for about 5 or 10 minutes, or use a code reader.

 

[niiice]

Just found this on a website. Any thoughts anyone?

DTC P0449 : Evaporative Emission (EVAP) vent Solenoid Control Circuit


This code is very common on this vehicle. The solution the majority of the time is to fix the wiring to the evap vent. The connector to the valve loses ground from the computer. At the pigtail, the wire turns green (corrodes) and loses the connection it needs. Replace the pigtail with #pt250. Be sure to use the updated valve and relocate the filter as well. If the wiring tests and looks OK, however, then suspect a faulty EVAP vent solenoid.​

Nicely done , but kindly be clear what a #pt250 is, A terminal? connector?

Response from mikevi
Replied on August 06, 2009
its the updated pigtail connection
Answered by bluelightnin6 (expert)

 

[niiice]

I have no schematic, but if you watch that video that I just added to the OP it may help you to use a test light on the connectors.

Also, did you reset the code and it came back? Or did it just never clear?

If you didn't clear it, it will take several drive cycles to clear on it's own. You can clear it by removing the negative of the battery for about 5 or 10 minutes, or use a code reader.

I cleared the code with my scantool and it came right back on. However the light stayed off until I started the truck back up. My scantool is not a very expensive one and I can not command the solenoid to turn on. Is there another way to that? I'm a wiz when it comes to wiring and issues like that. I just bought the truck at an auction, so I have not bought the shop manual from GM yet. I have several for my other vehicles. That does not help me in the meantime though. lol

 

[Bigredmariner]

Alright well I guess try to see if you have power, even if you can't command it off/ on. Engine will have to be running and just try a test light on one wire to ground, then the other. Since I don't know which should be hot.

The pigtail connector: Not sure of and wasn't aware that was a common issue. Wire corrosion on Texas vehicles is really rare, so I have no experience on it.

 

[niiice]

I will try tomorrow.I live in Ontario, Canada. Lots of snow and salt with that. I bought a new solenoid and noticed that it was already replaced once with the filter relocated. So the new part is going back tomorrow. Getting my $200 back. Thanks.

 

[Dartboy]

I was never able to get a test light to show power at my Evap Solenoid, I don't know if the broken wire to my Purge solenoid played any part in that. I was able to get the old Evap solenoid to click by connecting the solenoid directly to a battery after removal. And the little canister and vent tube passed air when I blew through them. I think you need a tool that can command the solenoids on and off. If you've replaced the vent and purge solenoids and still have the issue, it might be worth having a shop take a look at it.

 

[niiice]

Just wanted to post an update....I checked the connector and sure enough a pin sized hole in the orange wire and all green corrosion. Looks like someone probed the wire a long time ago, replaced the solenoid and never sealed the wire where they probed it. I have not gotten a new connector yet...GM said it would take 10 days to get it, so I'm stuck with taking the old connector apart and fixing it. I'm hopeful that that is it, but I have a diagram now to be able to trace it anyway.

 

[niiice]

I was never able to get a test light to show power at my Evap Solenoid, I don't know if the broken wire to my Purge solenoid played any part in that. I was able to get the old Evap solenoid to click by connecting the solenoid directly to a battery after removal. And the little canister and vent tube passed air when I blew through them. I think you need a tool that can command the solenoids on and off. If you've replaced the vent and purge solenoids and still have the issue, it might be worth having a shop take a look at it.

I don't trust very many shops. My wallet is not that big and I sure don't want to walk out with a $500 bill. I still have some sort of issue with the airbag. It says "Service Airbag" and the light is on. Don't even know where to start with that one.

 

[Dartboy]

It sounds very similar to what happened to me, vent solenoid was already the upgraded part with the remote vent, pinhole in a wire from a previous probe corroded later. I bet you're fixed now, though I'd check the wire near the purge solenoid for another pinhole.

Can't help you with the airbag, Sorry.

 

[GMCSIERRA1500]

IT Fixed my issues! Great Write up coming at you from the Great wide north.. Good thing too you had this, nearest dealer to me is 1 winter and a whole ICE road away! With the warm weather I was looking at having to do this next year! Now, I got no issues! Was able to have the parts flown in! Awesome!