So my 1999 Accord EX V6 threw a P0420 code (catalyst system efficiency below threshold) and it turns out these parts need replacing:

Vent Shut Valve
Vapor Canister Purge Solenoid
Vent Two-Way Valve

Firestone wanted almost $600 for the deal, I was like #&$% NO I'll do it myself.

I know the location of the purge solenoid in the car (right next to driver side shock housing) but I can't seem to find the other two parts on the vehicle. Maybe under/near the gas tank and such?

As far as ordering the parts, I found the purge solenoid and the shut valve on rockauto.com and autopartswarehouse.com, but I can't find this vent two-way valve to save my life...does anyone know what this thing is?

Any guidance is welcome, and again, once I find and order these parts, it should pretty much be smooth sailing, I've done a lot of DIY work, just never on the EVAP systems before.

Thanks in Advance.

 

It is right by the rear driver's tire. There is a TSB on how to fix the evap system. I helped a friend with the same car as you, the only tough part was removing the screws that hold on the two-way valve. I found it easier to take out the whole canister to do the job.

The code you posted is for the catalytic converter. Do you have other codes? If you aren't sure, most auto parts stores will scan the codes for free.

 

EDIT: Here is a post with it on our site:

https://www.hondaaccordforum.com/for...nce-not-27109/

 

Great thread, thanks for the link.

Okay so the shut valve is under the car, got it....any info on what the two-way valve looks like? I found a universal fit EVAP two way valve but I am not sure if that is what I am looking for.

This is the only code the car is showing, I got it scanned last week.

 

Ok I got it figured out and ordered the parts...the Vent two-way valve is actually called the Vapor Canister Purge Valve. Parts should get here Friday and I will post updates.

Thanks for the help, PAhonda!