Evaporative Emission System
Thread Starter
Burning Brakes
Joined: Nov 2008
Posts: 862
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From: Gaithersburg MD
Evaporative Emission System
Looking for a an explanation of the Evaporative Emission System in an 09 C6. Have a set of shop manuals but I can't find a description of how the system is implemented.
Also wondering what effect a FI boost system running at high boosts has on the system.
Also wondering what effect a FI boost system running at high boosts has on the system.
Race Director
Joined: Mar 2005
Posts: 10,399
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From: Austin Texas
From what I understand the Evaporative Emmisions control is just for fuel system vapors. Only keeps gas fumes from evaporating into the atmosphere.
There are 3 Federal Emmisions controls on the car.
Catalytic convertor for exhaust gases.
PCV valve for crankcase blowby.
Evaporative control for fuel fumes.
Forced Induction will cause more blowby into the crankcase from the higher cylinder pressure getting past the rings which means more dirty air going thru the PCV and into the intake. FI shouldn't affect the Cats or the Evaporative emmisions.
There are 3 Federal Emmisions controls on the car.
Catalytic convertor for exhaust gases.
PCV valve for crankcase blowby.
Evaporative control for fuel fumes.
Forced Induction will cause more blowby into the crankcase from the higher cylinder pressure getting past the rings which means more dirty air going thru the PCV and into the intake. FI shouldn't affect the Cats or the Evaporative emmisions.
Thread Starter
Burning Brakes
Joined: Nov 2008
Posts: 862
Likes: 0
From: Gaithersburg MD
Boost and EVAP
Seems to me that if the EVAP system is designed to expect 1 BAR or less at the intake manifold into which it vents (purges) the vapors, and if the manifold is running more than 1 BAR (i.e. FI boost) then the venting might change direction (i.e. there might be more pressure in the manifold than in the EVAP canister).
Just a thought, I guess it is up to the ECM to control the EVAP purge solenoid and perhaps it only does so today when the MAP reads a moderate to high vacuum condition?
Was looking for someone who really knows EVAP systems, and perhaps something about any changes that were made for the LS9.
Just a thought, I guess it is up to the ECM to control the EVAP purge solenoid and perhaps it only does so today when the MAP reads a moderate to high vacuum condition?
Was looking for someone who really knows EVAP systems, and perhaps something about any changes that were made for the LS9.
