This page is about how to control an evaporator canister - sometimes called as charcoal purge canister
The evaporator canister is ment as a temporary storage for gases from the fuel tank, instead of releasing them to atmosphere.
A simple valve controlled by GenBoard releases the gases to the intake given some conditions are met.
- low RPM
- low MAP
- warm engine
- closed-loop operation
- ... ?
Maybe with WBO2 closed loop control the condition becomes very simple.
Since we haven't seen much research/feedback on this (anyone want to contribute links or experience?) ...
I plan to install a solenoid to suck out the evaporator canister from time to time, using the same condition as for the variable intake with MembersPage/MarcellGal/EngineSwap/AirFeed : 1500..3000 RPM, 80..101kPa MAP. Actually planning to use same ECM output (a FET), but different solenoid (the 2 solenoid connected in parallel electronically).
google words: ...
pages: ...
Fero (or someone else), can you collect info about valve control that I believe was collected before but misplaced?
Hooked up the scan tool to an 01 civic, here is what I get.
- coolant above 70 c
- after that, the duty cycle changes based on rpm but it is graduall.
- Start car, 30 seconds or so later, approx 10% duty cycle. Leave it at idle, it creeps up to a max of about 30% in about 1 minute.
- Slight throttle input jumps to 30% then if maintained, will climb slowly to about 60%.
- Full throttle, is 100%.
- ON decel, duty cyle is 0%
- The more throttle, the more the dutycyle goes up, but it does it slowly, unless the throttle is moved quickly, then it will do a small, quick jump, but creep up the rest of the way to its full amount.
Thanx, very good info. A bit more complex than I thought. Apparently, it tries to avoid sucking the hell out of the canister (or adding extra air at low-load, whatever we call). Also, it changes slowly, so the EGO-correction can follow.
See also
- BoostControl : similar (small solenoid air-) valve is used