View Single Post
Old Sun, Feb-03-2013, 01:44:48 AM   #30
Unregistered User
Jrrrrrrr's Avatar
Join Date: Jun 2011
Posts: 789
In the garage:
Reputation: 0 Jrrrrrrr is on a distinguished road
Location: Tucson, AZ

United States

Default Re: Vapor Trails: code FD, evap valve stuck closed


I tried two things today and am finally happy to say, the DME has not set a pending code for "P0446/253/FD" -- IE, the dredded "evap-shutoff-valve-stuck closed." Before, I always had a pending FD code when the CEL wasn't illuminated. I could start it up after resetting the CEL, idle for a few minutres, and there would be a pending FD code when I scanned after shutting the car off.

I have driven through the drive cycle procedure and all my emissions monitors (besides SAI) are set ready -- including the evaporative monitor, which had never once shown a readiness status. I think I may have solved this problem.

First, I removed the carbon canister and blew compressed air through the inlet, outlet, and vent lines. I also blew compressed air into the shut-off valve's bore.

I noticed there was a fair bit of dust that came out of the shut-off valve bore when I blew compressed air into it. Then, with the purge valve in the engine bay energized, and I blew compressed air through the (pictured above) line in the trunk and effectively through a path all the way to the intake manifold.

Energizing the purge valve is important because if the purge valve isn't energized by 12v, there will be no air flow through it.

I'm not sure which one of these two things worked. Before, I had tried to blow compressed air through the purge-valve line while it was disconnected, so I know that was unclogged. I'm thinking perhaps there was a clog in the purge valve itself, or the rubber line between the valve and intake manifold. In essence, the O2 sensors would never detect fuel vapors from being combusted and the DME never completed the evaporative monitor.

Here's hoping this fix sticks and I can go get a smog check while only having to worry about passing the sniffer test!

Last edited by Jrrrrrrr; Sat, Jun-17-2017 at 01:27:51 PM.
Jump to top Jrrrrrrr is offline   Reply With Quote