5 Liter Eater

What am I missing out on if I remove this junk from my engine bay and tune out the codes?

Follow up question: Is it possible to use the EVAP line as a return line for a return fuel system?

B y r o n

How much performance are you expecting to gain?

5 Liter Eater

None. Just looking to remove clutter from the engine bay really. Figure .0001 1/4 mile gain from losing the 3/4# of weight from the hoses.

el es tu

If you end up removing the evap system, post a writeup please. Those of us who dont live in emissions states can benefit from removing the extra weight!

KENS80V

If you completely remove the EVAP system then you'll need to drill a small hole in your gas cap to vent the tanks. Then you run the risk of having a slight fuel smell in the garage.

The solenoid, plastic lines and canister are plastic. I just weighed the canister and solenoid at the tank, they're 4 lbs. The nylon vapor lines and solenoid at the manifold are maybe another 3 lbs.

It would be easier to just upgrade to the Z06 fuel module then to convert the EVAP vapor line to a return fuel line. You will have to drop the tanks anyways to accomplish this.

torquetube

We (Americans, anyway) all live in emissions states.

pmj341

Florida has no Emission testing of any kind!

5 Liter Eater

Wouldn't the evap hard line in the engine bay vent that, negating the need to drill a hole in the cap? I guess I'm not talking about the stuff in the tank, just the lines in the engine bay. I don't know why but it bugs me. Maybe it's not possible to remove that without removing the in tank stuff?

If I drop the tanks I'm putting in an aftermarket fuel system. Not ready to do that right now though.

I was kidding about the weight savings.

KENS80V

If you just left the line open in the engine bay then fuel vapors could possibly accumulate.

The vapor line goes back to the canister. Then a separate vapor line joins the canister to the tank. A solenoid is also located at the canister. That closes off the fresh air allowed into the canister when the Evap system tests itself. The ECM opens the solenoid at the engine and then looks at the vacuum produced in the fuel tank with the tank solenoid sealed off.

5 Liter Eater

I think I'll leave it alone...

BADZ

I'm getting a lot of pressure in the fuel tank and once I cracked the cap, pressure comes out but continuously until it cools down. Where is the canister/soleniods/valves located?

I also witness that my service fuel system comes on and my gauge reads empty..

Anyone??

CWHPARTS

YOULL GET A CEL BUT THAT IS EASILY TURNED OFF. I GOT RID OF MINE NO FUEL SMELL AND THE CAR IS .0001 FASTER THROUGH THE 1/4

Mike Farris

COH: What did you do? Remove it at the firewall and tune out the CEL?

CWHPARTS

removed the evap unit form the head and rerouted all the hoses. if your really intersted i can draw up a diagram of what i did (maybe not good with computers)

or if your around the store somethiem stop by id be glad to show you how i did it.

ShaneFap

Bump

haljensen

Florida is still part of the US isn't it? Federal (United States) laws apply. Emissons are Federal control, States can have harsher laws (California) but cannot have easier laws.

fred_S

COHPARTS that is a very good looking engine bay !

Bill Cole

would like to see that diagram

Dano523

Down and dirty, with the car shut off, solenoid at the charcoal canistor is open, Forward evap solenoid closed, to allow the tank to vent pressure that way. Since the fumes are being pushed through the charcol canistor, no gas smell/no raw petrol fumes into the atmosphere.

With car on, charcoal canister solenoid is closed, and tank is venting through the evap solenoid into the intake isntead to still not vent raw gas fumes into the atmosphere.

At start up, both solenoids are help closed so the car can not only check the solenoids to makes sure they have the needed resistance to show they are connected/not burnt out, but the pressure in the system to make sure that the gas cap is not leaking as well.

As for the charcoal canister, it's above the tanks.

As for pulling the charcoal canister and evap lines, make sure to install one way check valves, so fuel is not allowed to pour out the top of tank in case of roll over.

C5 Diag

This operation must be different on the C6 vs. the C5….on the C5 the vent valve is normally open and the purge valve is normally closed at start up…with the ECM runs it’s EVAP Monitor Test it closes the vent valve and opens the purge valve…the fuel tank is drawn into a vacuum and at a certain value it commands the purge valve closed…the vacuum decay (actually voltage change vs time) determines if there is a “small leak” or “large leak”…if the vent valve sticks closed it’s difficult to fill the gas tank at the pump…if the purge valve is stuck open you will have a rich condition and then a lean one as the canister burns off those gas fumes after fill up…you basically have a vacuum leak now.