is this the fuel tank vent? in the red box, is that the computer controlled vent solenoid?

does the vent tube currently going to my charcoal canister goto that? if not, what goes there?

 

yeah its just the evap.. i removed mine from the ls1 and just let it vent to atmosphere out the back .. you can run a hose from the hardline that goes into the evap into that if you are using the 3rd gen tank

 

That would be the purge solenoid. The vent solenoid is attached to the fuel tank on the LS1 vehicles. I am not sure on how to incorporate it to your stock evap system. Maybe someone else can chime in here. I plan on trying to get an LS1 fuel tank and hooking up the complete new style EVAP system. Good luck.

 

A little more info that might be able to help you hook it up:

The evaporative emission (EVAP) control system limits fuel vapors from escaping into the atmosphere. Fuel tank vapors are allowed to move from the fuel tank, due to pressure in the tank, through the vapor pipe into the EVAP canister. Carbon in the canister absorbs and stores the fuel vapors. Excess pressure is vented through the vent line and EVAP vent valve to the atmosphere. The EVAP canister stores the fuel vapors until the engine is able to use them. At an appropriate time, the control module will command the EVAP purge valve ON open, allowing engine vacuum to be applied to the EVAP canister. With the EVAP vent valve OFF open, fresh air will be drawn through the valve and vent line to the EVAP canister. Fresh air is drawn through the canister, pulling fuel vapors from the carbon. The air/fuel vapor mixture continues through the EVAP purge pipe and EVAP purge valve into the intake manifold to be consumed during normal combustion.

This is related to the LS1 EVAP system.

 

ive owned a few old cars without charcoal canisters... and i dont want the vapor smell that accompanys a atmosphere vent...

if i hook my vapor line to that, does the LS1 use the pressure seen at the purge solenoid to know when to vent excessive pressure? is there a sensor there?

or is it somthing in the tank?

basicly, if tank pressure becomes high, i want it to vent into the engine. but otherwise, i want it sealed.

does this allow air into the tank too?

i BELIEVE the LS1 has a charcoal canister mounted above the fuel tank... but im not sure... if it does, then im going to assume thats how the tank gets air without releasing fumes... correct?




basicly, im just trying to figure out how i want to do the evap system to allow the fuel system to operate properly.
im not after emissions compatability.... but i dont want to vent my gas to the air.

 

The sensor is mounted in the 4th gen fuel pumps. It is mounted right next to the plug in for the fuel pump and level sensor on top of the fuel pump. That gives the reading to the pcm which tells it when to vent, when to purge etc.

you would have to have the sensor so the pcm would know when to comand on the purge solenoid so that the vacuum would pull the vapors out of the cansiter.

 

thank you.


by anychance, can you tell me how you did your fuel vent setup?
looking at all this, im thinking about just getting a small charcoal cansiter ment for a older carb car, mounting it at the rear of the car (for space reasons) and having just a charcoal filter to keep the vapors in.... very basic vent system.

 

yes, and I believe the it has a line that runs to the front of the car. but I only used the LS1 tank for my LT1 swap and I removed the charcoal canister as well as all other emmissions equipment.

 

right now i just took the stock line that runs to the canister and just wrapped it around the filler neck to keep debris from getting in and just let it vent. I will be getting a 4th gen tank and will hook up all evap correctly at a later date(when ever i get a killer deal on it all).

 

so are you saying that the 4th gen tank and evap system is a direct bolt in, or is there fabrication needed to install these parts into a 3rd gen?

 

the 4th gen tank has the evap built into it. I only used the tank for the tank and the pump not the evap setup, it has some electric connections to it that I never worries about so I don't know. I looks like it is either PCM or BCM controlled.

 

But does the tank itself bolt in, and the lines hook up ok?

 

From what i have read, the tank bolts in, but you have to trim the fill neck slightly. If you go to the LS1 tank, you would not be able to use the stock lines, LS1 = returnless fuel system( no return line) I would just get all the LS1 lines to go with the tank and use them. You might be able make the stock lines work, but i dont know for sure and it would probably have to be rigged with rubber fuel line. Which i would not do.

 

The reason that I ask is because I have all of this stuff on my 98Z28 that I am using for the donor car here.

 

Actually the LS1 does have a return line, just take a peak near your tank to find out.

 

it is not a true return line, the fuel pressure is not regulated there. The fuel pressure is regulated intank.

 

Thanks for all the help, I think I am going to put all of the 4th gen stuff in, screw it.

 

yes, but it still has a return line