keep or kick the EVAP on a returless fuel system
#1
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Hey Folks
I'm preparing to sell the the old engine and all the stuff I'll have no further use after the Swap. (i have no room)
Victim is an F-Body 1991 Firebird 3.1L V6 (LH0)
The new engine will be an 5.3L GEN IV AFM Flex Fuel all aluminum (LC9) with a returnless fuel system. I'll use an 1998+ Corvette Regulator/Filter installed under the left hand back seat.
Do i still need the Vapor Canister? I didn't even find a connection to the ECM on wiring diagrams for the purge action.
I'm preparing to sell the the old engine and all the stuff I'll have no further use after the Swap. (i have no room)
Victim is an F-Body 1991 Firebird 3.1L V6 (LH0)
The new engine will be an 5.3L GEN IV AFM Flex Fuel all aluminum (LC9) with a returnless fuel system. I'll use an 1998+ Corvette Regulator/Filter installed under the left hand back seat.
Do i still need the Vapor Canister? I didn't even find a connection to the ECM on wiring diagrams for the purge action.
#2
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I would use the Canister to keep the fuel Tank vented and to keep the Gas fumes down.
I used my old one from the Chevelle (there are smaller ones out there) and just used the vacuum sourse from the EVAP port and did away with the LS1 EVAP solenoid/system.
Not sure what the new 5.3L will have, but it sounds like a good project for your 91... keep us posted.
I used my old one from the Chevelle (there are smaller ones out there) and just used the vacuum sourse from the EVAP port and did away with the LS1 EVAP solenoid/system.
Not sure what the new 5.3L will have, but it sounds like a good project for your 91... keep us posted.
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Note: I only have the LS1 Engine Kit Istallation Guide and the Web for info. Helms Manual will fallow soon, just not yet
#4
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No on the Controller, it is connected to the Red PCM Connector #34.... I am not sure what or how your new LC9 is equip'd or wired..
But on a LS1 F-Body.. the EVAP (Solenoid and valve) is connected to a vacuum port on the driver side of the intake and lay above the #1 cyc and next to the fuel rail. It is connected into the Engine harness and is controlled by the PCM. (see LS1 guide, page 16, 1st photo, just above the coil of #1, that is the EVAP for a LS1.)
What I did was just did away with the EVAP Solenoid and valve, left my Canistar connected to the fuel tank (as it would be for my 71 Chevelle) and then just connected a vacuum port of the canister to the port were the EVAP was connected to.
But on a LS1 F-Body.. the EVAP (Solenoid and valve) is connected to a vacuum port on the driver side of the intake and lay above the #1 cyc and next to the fuel rail. It is connected into the Engine harness and is controlled by the PCM. (see LS1 guide, page 16, 1st photo, just above the coil of #1, that is the EVAP for a LS1.)
What I did was just did away with the EVAP Solenoid and valve, left my Canistar connected to the fuel tank (as it would be for my 71 Chevelle) and then just connected a vacuum port of the canister to the port were the EVAP was connected to.
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Hm... this is odd. My Guide for the LS1 (PN 88959384 REVISED 9/1/01) says "Skip Shift Solenoid Control (M/T) or 3-2 Shft Sol (A/T) on #C1 Red Connector ECM Term 34.
I'll repost my Question on the TGO Board. If nothing clear emerges, I'll keep the canister until i've got the actual engine in front of me plus service manual of the correct donor vehicle and year.
I'll repost my Question on the TGO Board. If nothing clear emerges, I'll keep the canister until i've got the actual engine in front of me plus service manual of the correct donor vehicle and year.
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#7
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Originally Posted by five7kid, Third Generation F-Body Message Boards
The vapor canister vents the tank as the fuel level drops, and lets the tank breathe with temperature changes. It doesn't have anything to do with fuel return. So, yes, keep it.