Carbon canister and EFI

[Bitterman]

Good evening everyone,

I'm in the middle of installing a Sniper EFI in my 1980 Olds Cutlass. I have a new line running from the vent nipple on the sending unit to the front of the car to hook to a carbon canister. Here is where I need advise.

I have two carbon canisters that I can use. Which one is best for an EFI setup o does it matter?

Second question is where do I run a rubber line from the carbon canister to the engine/EFI setup?

Thank you

 

[Clone TIE Pilot]

EFI requires a EVAP purge solenoid. Does the Holley sinper system even have a provision for EVAP? Most aftermarket EFI systems lack provisions for emissions equipment.

 

[Jim Rockford]

the second style is the one you need, The smaller pod on the right uses a line from the Ported vacuum port to open the canister and allow the engine to suck in the fuel vapors. The style on top requires the use of a failure prone really bulky valve on the purge line to work otherwise if you just run a line from the can to the TB you will suck vapors 100 percent of the time and the can wouldnt collect them when its off.

 

[Jim Rockford]

Why Does Your Corvette Smell Like Gas? - Corvette Central Tech Blog

Read more about Why Does Your Corvette Smell Like Gas? at Corvette Central Tech Blog

tech.corvettecentral.com

 

[Northernregal]

I used the top style. Put a small engine canister fuel filter inline as a restriction/filter. No fuel smell and the air bleed when tuning IAC was minor.

 

[Bitterman]

Thanks everyone. Good info and thanks for the article. Looks like there are options which is good. I need to check out both canisters to make sure at least one of them is good to go. I think someone posted info on here about how to rebuild/refresh a canister. I'll have to search it out.

Thanks again. I'll try to report back how it goes.

 

[Jim Rockford]

you can get new activated charcoal from pet stores in the aquarium section.

 

[Bitterman]

Nice! I'll check that out. I'm sure sitting on a shelf for 10 years that the charcoal could use a refresh. Thank you

 

[Bitterman]

Nice! I'll check that out. I'm sure sitting on a shelf for 10 years that the charcoal could use a refresh. Thank you

Well, I'll be rebuilding the carbon canister this week but another issue has come up.

I put 5 gallons of fuel in my gas tank in preparation for a first start with a holley sniper system. 10 minutes after putting 5 gallons in the tank, it started spitting fuel out the vent tube from the fuel tank. My fuel tank is a EFI tank from an 87 monte carlo that had EFI from the factory. My vent line is hanging above the rear axel and not currently run to the front of the car yet. It does not spit out fuel if the gas cap is off or loose. If I tighten the gas cap, it will leak fuel from the end of the vent line. I have tried two stock gas caps and both when tightened cause the leak. I have a 3 line spectra sending unit installed in the fuel tank.

What could be causing this vent line fuel leak? Do I have something setup wrong? Can a stock fuel cap be rebuilt or could it just be a bad fuel cap not allowing the tank to breathe?

 

[Northernregal]

Well, I'll be rebuilding the carbon canister this week but another issue has come up.

I put 5 gallons of fuel in my gas tank in preparation for a first start with a holley sniper system. 10 minutes after putting 5 gallons in the tank, it started spitting fuel out the vent tube from the fuel tank. My fuel tank is a EFI tank from an 87 monte carlo that had EFI from the factory. My vent line is hanging above the rear axel and not currently run to the front of the car yet. It does not spit out fuel if the gas cap is off or loose. If I tighten the gas cap, it will leak fuel from the end of the vent line. I have tried two stock gas caps and both when tightened cause the leak. I have a 3 line spectra sending unit installed in the fuel tank.

What could be causing this vent line fuel leak? Do I have something setup wrong? Can a stock fuel cap be rebuilt or could it just be a bad fuel cap not allowing the tank to breathe?

Sounds like your vent is connected to the return line. The return goes to the bottom of the tank and would push fuel up with expansion.