I'm probably literally the only person to want to do this, and I'm sure this will lead nowhere, but I'm hoping someone can provide some clarity on how I can keep the Honda EVAP system and use the GM LS1 PCM to operate it.

Unfortunately I'm not quite smart enough with electronics to make this happen, but I am knowledgeable enough to understand that this *can* work. I just don't know how to do it.

The BMW guys have done it, or rather have been the only swap group to care enough to figure it out. I know I'll need to wire/mod in a GM fuel tank pressure sensor and trick the fuel level sensor with a resistor, but other than that I'm not sure exactly how the Honda system operates in stock form and I don't know what some of the Honda sensors even are (back there with the evap system).

Basically I want to use the LS1 PCM to operate the stock LS1 purge solenoid on the motor in conjunction with the stock s2k EVAP system under the car.

Can anybody confirm that the stock s2k purge solenoid on the motor operates at 0-5v, and is normally "closed" with 0 reference voltage?

What about all the other Honda components that are still hooked up to, some of them controlled I'm sure by the Honda ECM? Honda fuel tank pressure sensor, EVAP Bypass Solenoid Valve, EVAP Canister Shut Valve?

My concern is that each of these sensors will need to be properly actuated for the entirety of the system to operate. I can't find enough detailed information about any of these to make a strong determination on if I'll be able to make it work.

Info on the GM system is abundant, so no problems there. It's the Honda system I'm curious about.

I don't want to constantly be smelling fuel or having to worry about pressure/venting the gas cap etc.

Seems like most of the S2k community just decides to trash the EVAP system so the information is very limited when searching. All I can find are how to get rid of it.

EVAP systems are great at venting the fuel tank and controlling fumes. Why anybody would rather smell fuel and have a hard time filling up gas tanks rather than just keeping the system is hard for me to understand.

If a forum member has more detailed information on the Honda evap system, I'd love to hear it.

 

The stock AP1 has a purge solenoid close to the intake manifold and it's normally closed at 0V and opens at 12V, it's directly controlled by the ecu.
As for all the other sensors and functions the AP1 service manual is available online if you do some searching and it describes the EVAP system very well.

 

Why would you have a 'hard time filling up gas tanks'? Are you planning to seal the tank with no ability to exchange pressure with the atmosphere?

Also, gasoline smells really good.