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'96 Outback 2.2/F350
158 Posts
Discussion Starter #1
Attempting to Darken 443 CEL on a '98 2.5 stick.
Just evaluated evap system.
Vacuum-pump tested all engine-compartment evap hoses/fittings, replaced as necessary. Now trying to confirm component functionality/isolate culprit.
Compared '98's values to a '99 "test" car (=similar system components, no codes),


Purge Solenoid Valve (PSV)- Tested with engine cold/hot, off/idle/throttle but it stayed closed on '99 under all those conditions.
Under WHAT conditions is it designed to open and allow throttle-body vac to the charcoal canister? Testing PSV voltage? Testing a charcoal canister?

Pressure Sources Switching Solenoid Valve (PSSSV)- The intake manifold's vac-feed was open to the (barometric?) pressure sensor (PS) under all above test conditions. The PSSSV was never closed.
Under WHAT conditions is the PSSSV designed to close and prevent intake-vac to the PS? Testing PSSSV voltage?

Further, judging by the emissions diagrams on the '98 v '99, the PSSSV on the '99 has three hose-taps versus the 2 on the '98. BUT, this '98 has the three-tap PSSSV, so the question is: adhere to the '98 diagram and just cap-off the third hose-tap on the PSSSV or route it like a '99?
From a smog-shop perspective, I'm inclined to copy the '98's affixed sticker diagram.

Replaced Fuel Cap. Still 443. Wondering if audible de-pressurization when you remove (unscrew) the fuel cap necessarily confirms a good cap and/or any other emissions system components?

Finally, in a Gen I is the "vent valve" that everyone references located above the tank near the fuel-pump cover, or in-tank? That sounds like the next dance at this party.

Thought: if one retrofitted a leak-down tester onto the fuel filler nozzle, couldn't you recreate the system's pressure in order to assist isolating component/line issues from aft-to-fore? Engine-off, it seems like you'd be able to hear air leaking from any failed hoses and/or determine if there are flow blockages. Thoughts?

Many Thanks!

PS- As annoying as it is trying to correct emissions systems issues, I try to remind myself that the grief, effort and expense is worthwhile.
The grandchildren of our grandchildren.
Now if we can just get our AWD's up to 50mpg+... or electric!
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