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EVAP systems - how many different types? 2000 Silverado


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My 2000 Silverado has an issue with the evap system that is causing the P0449 trouble code.  

 

I've watched several videos and it looks kind of simple to fix the issue, except my truck seems to be different.  Most videos show a small canister behind the fuel tank.  Mine however has a larger canister in front of the tank - I think.  Am I looking at the right thing?  Two fuel lines seem to go to it.

 

A mechanic said the truck had to be upgraded to fix the trouble code - apparently the old parts are no longer available.  I'm wondering if old parts might be available via Ebay, Amazon, etc - things he can't do (because he has to warranty his work) but as the owner I might be willing to do.

 

Am I even looking in the right place?

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Parts are readily available local and online.

There are discussions about a relocation recommendationfrom gm that moved items and pleaded the atmosphere intake higher up.

This was to resolve issues associated with overfilling the tank or driving in high water.

Both versions of the parts are available.

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P0449 is an electrical issue with the vent solenoid  ( the pic is of the canister not the solenoid ), wiring or pcm.  Most likely the solenoid but needs to be diagnosed. The solenoid is hidden behind the driver side of the cab. Between the cab and box. Kind of a bitch to get to.

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1 hour ago, tbarn said:

P0449 is an electrical issue with the vent solenoid  ( the pic is of the canister not the solenoid ), wiring or pcm.  Most likely the solenoid but needs to be diagnosed. The solenoid is hidden behind the driver side of the cab. Between the cab and box. Kind of a bitch to get to.

I found it. On top of the gas tank it looks like. How on earth do I get to it ?

 

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Looking at this, I might not even need to get the old one out to replace it.

 

Most upgrades/replacements have this thing relocated anyway - some using heater hoses and other things.  What I'm thinking is if I can get the wire off of the old one, I can unhook and/or cut the line to it and then connect the new one.  Old one can just kinda sit there.

 

For that matter, worst-comes-to-worst I can even cut the wire and put a new plug on it.

 

I'm a minimalist so I prefer to strip off anything that doesn't do anything, but in this case I might just leave the old one in place.  

 

But in the interest of due diligence I plan to replace the fuel cap first.

Edited by SC Tiger
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The canister and solonoid valve can be separated and custom setups used (assuming state inspection allows)

The lines from the tank and to the engine should be fuel grade capable as they will be carrying fumes and possibly liquid fuel. The atmosphere line can be nearly grade (for under vehicle) as it will carry air without any high pressure or vacuum.

Floor jack, 2x4 and you Might be able to lower the front end of the tank to gain access. (Have used this to lower rear end to change fuel pump).

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19 hours ago, sefiroxx said:

The canister and solonoid valve can be separated and custom setups used (assuming state inspection allows)

The lines from the tank and to the engine should be fuel grade capable as they will be carrying fumes and possibly liquid fuel. The atmosphere line can be nearly grade (for under vehicle) as it will carry air without any high pressure or vacuum.

Floor jack, 2x4 and you Might be able to lower the front end of the tank to gain access. (Have used this to lower rear end to change fuel pump).

No state inspection in SC.

 

Amazon does sell a kit that relocates the valve.  Seems to have everything.  But it's $80 and I don't know how good the valve in it actually is.

 

Where I work, we have used fuel vapor lines that actually state "not for fuel" or something like that.  I assume vapors are okay though......:D

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The gm relocation recommendation resulted from too many customers overfilling their tanks which apparently allowed liquid fuel to travel through the line to the evap canister during operation.

After that, it's unlikely but not 0 odds that the engine vacuum could pull liquid through the line from the solenoid to the intake. So, if it's the SO's car, fuel grade. . . .

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17 hours ago, sefiroxx said:

The gm relocation recommendation resulted from too many customers overfilling their tanks which apparently allowed liquid fuel to travel through the line to the evap canister during operation.

After that, it's unlikely but not 0 odds that the engine vacuum could pull liquid through the line from the solenoid to the intake. So, if it's the SO's car, fuel grade. . . .

I think I’m gonna just order the kit on Amazon that relocated the whole thing. $80 and seems to have everything I need but I’ll look at it a little harder. Probably a new plug too but gotta figure out what it’s called. 

 

Got it any help on that?

 

As for now I don’t go over 3/4 tank. Don’t drive it much anyway. I usually go non ethanol or put Sta-bil in it because it sits so much anyway. 

 

Fuel in the vacuum is funny because I was having a rich condition misfire and having a hard time finding the source. Finally pulled the vacuum line to the fuel pressure regulator and a column of gas shot up about an inch - forgot to relieve the pressure first (oops!). 

 

New one one from Auto Zone (all I could find available right then) and she’s running well. Just want to get that light out but if the truck can pull gas through this thing to the intake that turns up urgency a but. 

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On 6/29/2019 at 3:19 PM, sefiroxx said:

The gm relocation recommendation resulted from too many customers overfilling their tanks which apparently allowed liquid fuel to travel through the line to the evap canister during operation.

After that, it's unlikely but not 0 odds that the engine vacuum could pull liquid through the line from the solenoid to the intake. So, if it's the SO's car, fuel grade. . . .

I got all I could find which was heater hose. May change it later but it let me re-mount the solenoid on top of the Evan canister with a mondo zip tie.  Didn’t seem right leaving it off altogether. 

 

It turns out that something had eaten the wire to the solenoid. It was missing from the harness to the plug. I’ve ordered a new plug from Amazon and pulled the two wires out of the bundle and have them ready to connect to the new plug when it arrives. I tried to reuse the old plug but I couldn’t make it work. 

 

I figure the the odds of the wire being eaten AND the solenoid going bad are kinda remote so I reused the old solenoid for now. If it still gives a code I’ll get a new solenoid. 

 

I am getting power at the two wires that go to the solenoid. 

 

 

 

 

 

 

 

Edited by SC Tiger
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Something else I’m trying to reconcile is that a mechanic quoted me $300+ for this. Said they had to update the system to fix it. I assume they mean the two-piece solenoid system. 

 

I know they can’t -as a professional shop - do what I did but that still seems high. Maybe they know something I don’t. 

 

This is shop has always hit me straight. Maybe that was a worst-case estimate.  He typically uses either OEM parts or the same brand as OEM - ie might use Denso parts on a Honda instead of parts from Honda - which are made by Denso. 

Edited by SC Tiger
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