Evap question

scriptedmind · 08-26-2009, 09:47 PM

I wasn't gonna bother asking this but curiosity is killing me.

I'm running the truck intake which has an evap line running to it. I was gonna hook it up on my truck but realized that I don't have a plug on my harness for it. How will that effect my mpg and what do I need to do with the solenoid deal on the intake and the evap line on the truck to properly block this stuff off?

I told Jared that I wasn't running emission stuff when he built my harness but I guess i forgot to mention what I was gonna do with the evap stuff and I'm guessing it was omitted because I told him no emissions.

NCRides · 08-26-2009, 10:56 PM

If Jared built the harness without evap provision you will have to run without and use a vented cap, since the evap only controls the vacuum or pressure of a non vented fuel tank it doesn't control the rate of fuel consumption so your mpg won't be effected. the thing that an evap does is not allow gas fumes (voc's) to escape into the atmosphere and so your truck will not be emissions legal in some states, oh well....I would just cut the line off the valve on the intake and cap it with a rubber cap that can be purchased at most parts stores,same for the line going to the tank.....oh hey I have at work some block off plates that came on a replacement AC condensor , I'll check tomorrow to see if it will fit in place of the intake valve... I'll let you know

scriptedmind · 08-26-2009, 11:32 PM

Glad I asked this question now lol. I guess pressure in the gas tank would be a major issue. No biggie i guess, i needed a new gas cap anyway. I just want to make sure that my ride is safe.

NCRides, thanks for the info. definitely let me know about the block off plates.

As far as emissions go, i would have gladly run emission system on my truck but Sanderson doesn't sell headers with an EGR bung and i cant weld so i opted to have it all removed. AR doesn't check anyway.

Petro · 08-27-2009, 12:09 AM

I thought the line ran from the Evap Canister to the soleniod then to the intake????

scriptedmind · 08-27-2009, 12:34 AM

I don't really know about how the evap system works past the cab but here is a pic of my intake. There is some masking tape on the solenoid that we put there to keep dirt and bugs out for right now.

Yes i know the engine is filthy which is why i don't have a build thread on here, i don't want anyone to see it like that. I haven't had access to water where my truck is sitting so i couldn't wash anything. I will pressure wash it once it's complete.

p.s. the engine came out of a Z71 that was rolled out into a muddy field if that explains the dirt.

scriptedmind · 08-28-2009, 11:03 AM

Damn it keeps bugging me that I won't have an evap line like everyone else on here.

I know it doesn't really matter but I hate having to buy a special gas cap to compensate for something that the truck had stock that I removed. If it came with an evap line i would like to keep the evap line so that it's as close to stock as possible.

I wonder how hard it would be to modify Jared's harness to install some wiring for the evap solenoid? Anyone know how to pin those wires in the plugs for the ECU?

NCRides · 08-29-2009, 10:01 PM

so what are you going to do?..... I'm sure Jared will make a secondary harness for your evap it wouldn't take much just two wires running back to the evap canister and two wires to the solenoid on the intake and you could pin them into the pcm harness of course you should run 02 sensors also but you would need the wires for them and install bungs in the exhaust pipes and get the sensors...naw just get a vented cap and be done with it

mr spree · 08-29-2009, 11:01 PM

My harness that i just got has the evap on the wiring harness... do you have emissions where you live?

08-26-2009, 09:47 PM	#1
scriptedmind Registered User Age: 23 Join Date: Apr 2007 Posts: 119 Location: Little Rock, Arkansas User is: OffLine	Evap question I wasn't gonna bother asking this but curiosity is killing me. I'm running the truck intake which has an evap line running to it. I was gonna hook it up on my truck but realized that I don't have a plug on my harness for it. How will that effect my mpg and what do I need to do with the solenoid deal on the intake and the evap line on the truck to properly block this stuff off? I told Jared that I wasn't running emission stuff when he built my harness but I guess i forgot to mention what I was gonna do with the evap stuff and I'm guessing it was omitted because I told him no emissions.
	[Reply w/Quote]

08-26-2009, 10:56 PM	#2
NCRides Registered User Age: 53 Join Date: Dec 2005 Posts: 294 Location: Amesbury Mass User is: OffLine	Re: Evap question If Jared built the harness without evap provision you will have to run without and use a vented cap, since the evap only controls the vacuum or pressure of a non vented fuel tank it doesn't control the rate of fuel consumption so your mpg won't be effected. the thing that an evap does is not allow gas fumes (voc's) to escape into the atmosphere and so your truck will not be emissions legal in some states, oh well....I would just cut the line off the valve on the intake and cap it with a rubber cap that can be purchased at most parts stores,same for the line going to the tank.....oh hey I have at work some block off plates that came on a replacement AC condensor , I'll check tomorrow to see if it will fit in place of the intake valve... I'll let you know Last edited by NCRides : 08-26-2009 at 11:05 PM.
	[Reply w/Quote]

08-26-2009, 11:32 PM	#3
scriptedmind Registered User Age: 23 Join Date: Apr 2007 Posts: 119 Location: Little Rock, Arkansas User is: OffLine	Re: Evap question Glad I asked this question now lol. I guess pressure in the gas tank would be a major issue. No biggie i guess, i needed a new gas cap anyway. I just want to make sure that my ride is safe. NCRides, thanks for the info. definitely let me know about the block off plates. As far as emissions go, i would have gladly run emission system on my truck but Sanderson doesn't sell headers with an EGR bung and i cant weld so i opted to have it all removed. AR doesn't check anyway.
	[Reply w/Quote]

08-27-2009, 12:09 AM	#4
Petro Registered User Age: 24 Join Date: Oct 2008 Posts: 2,544 Location: Savannah, GA User is: Online	Re: Evap question I thought the line ran from the Evap Canister to the soleniod then to the intake????
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08-27-2009, 12:34 AM	#5
scriptedmind Registered User Age: 23 Join Date: Apr 2007 Posts: 119 Location: Little Rock, Arkansas User is: OffLine	Re: Evap question I don't really know about how the evap system works past the cab but here is a pic of my intake. There is some masking tape on the solenoid that we put there to keep dirt and bugs out for right now. Yes i know the engine is filthy which is why i don't have a build thread on here, i don't want anyone to see it like that. I haven't had access to water where my truck is sitting so i couldn't wash anything. I will pressure wash it once it's complete. p.s. the engine came out of a Z71 that was rolled out into a muddy field if that explains the dirt. Last edited by scriptedmind : 08-27-2009 at 12:35 AM.
	[Reply w/Quote]

08-28-2009, 11:03 AM	#6
scriptedmind Registered User Age: 23 Join Date: Apr 2007 Posts: 119 Location: Little Rock, Arkansas User is: OffLine	Re: Evap question Damn it keeps bugging me that I won't have an evap line like everyone else on here. I know it doesn't really matter but I hate having to buy a special gas cap to compensate for something that the truck had stock that I removed. If it came with an evap line i would like to keep the evap line so that it's as close to stock as possible. I wonder how hard it would be to modify Jared's harness to install some wiring for the evap solenoid? Anyone know how to pin those wires in the plugs for the ECU?
	[Reply w/Quote]

08-29-2009, 10:01 PM	#7
NCRides Registered User Age: 53 Join Date: Dec 2005 Posts: 294 Location: Amesbury Mass User is: OffLine	Re: Evap question so what are you going to do?..... I'm sure Jared will make a secondary harness for your evap it wouldn't take much just two wires running back to the evap canister and two wires to the solenoid on the intake and you could pin them into the pcm harness of course you should run 02 sensors also but you would need the wires for them and install bungs in the exhaust pipes and get the sensors...naw just get a vented cap and be done with it
	[Reply w/Quote]

08-29-2009, 11:01 PM	#8
mr spree Whats this for? Age: 20 Join Date: Jan 2008 Posts: 1,013 Location: Spokane WA User is: OffLine	Re: Evap question My harness that i just got has the evap on the wiring harness... do you have emissions where you live?
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