So when I get home from a drive. Park the car . Turn the car off, you can still hear the purge working when you turn the car off. It’s going to purge still after just turning the car off. It eventually stops , which never know exactly when but Purge definitely still happens very faintly after a drive and car is off and parked.

 

Sure, maybe for 30 to 60 seconds; still not enough to matter I don't think.

Also keep in mind that results may vary from application to application. Given how the fuel pump is run on the s2000 in aftermarket applications (unless brushless with a controller); it's always on at full blast. If you have a higher fuel demand and/or run your car at a higher base pressure like I do (60 psi) you're going to be running a larger pump working much harder than the dinky stock fuel pump, drawing much more current and producing quite a bit more heat, heating the fuel up/. Couple that with your environment like maybe FL or the Midwest on a hot summer day and you're going to have a scenario where you can potentially build up quite a bit of pressure in the tank. Remember, Gasoline starts to boil at 100-140 degrees F, so unfortunately it's a scenario that will occur on very hot days with high-current draw pumps running at higher base pressures. The only way I could see to alleviating this is by running a fuel cooler on the return line.

I'm running a Walbro 535 in my car at 60 psi base pressure, and 20 lbs of boost, so roughly 80 psi WOT, and on a hot summer day the purge valve definitely does as you described; still venting after you shut the car off, but it does stop after roughly 30 seconds to a minute, vs. on colder days where it stops almost immediately. I ran my car on ethanol for a majority of the summer, and didn't hear the purge valve nearly as frequently due to the higher boiling point of ethanol (180* F), but once I switched back to running gasoline I did notice the valve vents much more frequently and for longer on hot summer days for sure.

 

So I guess my valve relieves pressure through out the night because I hear the small hissing around 2-3 hrs after getting home . I check the sound before I go to bed and i can still hear it. Sucks. Also, smell gas fumes while driving as well. I guess I’ll have to deal with it

 

Hey Kyle, will the check engine light come on if the EVAp system is removed?

 

Absolutely, yes, if you're on your OEM ECU. Most people delete the evap when they go standalone, and you obviously won't get a CEL in that instance.

Fortunately there's places that sell a wire-in simulator/CEL eliminator for people who delete their evap and still run the OEM ECU.

Honda and Acura EVAP Simulator

 

Don't leave the vent tube open like I did, run it somewhere like the subframe. Don't want fumes filtering up to the cabin.

 

ty for this sticky.

 

I added a charcoal canister this week, this one mounts to the same holes as OEM Plumbed it's purge through factory hardline to intake.

 

I was thinking about removing all these stuff on my European sold 2003 car so took a closer under it.
There is so much less stuff under there, so not really sure if it is worth it on our cars,
Here is a parts diagram for reference https://www.parts-honda.uk/honda-car...__0400/3/20727


Maybe useful info if someone would like a more simple OEM solution.

 

I was fighting post evap delete smells for years around 2016-2017 (doing everything possible)...i'm running #4 and 5 on an European ap1 fuel tank...the fuel tank has a simplified OEM bidirectional vent/check valve. when pressure builds it allows fumes out like when its really hot after extended running, but it allows fresh air to come in to replace fuel being used by the engine during running. the only thing i did was add a breather on the exgress of 4 to the front of the car just so dust or debris doesn't make its way in. currently no smells when things cool down at all.