Emission System CEL - Help!

vintageant · #1 (**permalink**) 03-21-2006, 01:30 PM

OK, I've just registered as a new member and here's my first question. I've been a Ford trucks -> Aerostar forum user for years. Very helpful! Anyway, the Aerostar is now gone, replaced bya 2002 Highlander V6 2wd with 60K miles. Two days and less than 20 miles after purchasing, while parked at the railroad crossing waiting for a train, the check engine light comes on.
The codes pulled via OBD-II are:

P0440 Evaporative Emission Control System
P0441 Evaporative Emission Control System Incorrect Purge Flow
P0446 Evaporative Emission Control System Vent Control Circuit

So now what? Help!

nhparrot · #2 (**permalink**) 03-21-2006, 02:17 PM

see attached

vintageant · #3 (**permalink**) 03-23-2006, 07:53 PM

Well, thanks for the technical pdf files, NHParrot! I was rather hoping for some anecdotal feedback from owners who have encountered the same problem, and fixed it. I checked the easy one, making sure the gas cap is on good and tight, but as a process of easy elimination what is the next step in your experience?
We cleared the CEL, and drove about 30 miles before the CEL came on again, and it has stayed on.
Ideas?

mustang67408 · #4 (**permalink**) 03-24-2006, 12:21 AM

Make sure the hose at the CCV valve is conected. It is bolted to the top of the air cleaner lid, also make sure that both ends of the hose are connected and someone didnt accidentaly disconnect it while changing or checking the air filter.

vintageant · #5 (**permalink**) 03-24-2006, 06:32 PM

Mustang,

That was it! Totally disconnected! Reattached and will give it a couple of days to ensure light stays off before I report back. We're a Honda, Ford, Subaru family and this is our first Toyota, so just starting to learn.

Thanks!

mustang67408 · #6 (**permalink**) 03-24-2006, 06:51 PM

Quote:

Originally Posted by vintageant

Mustang,

That was it! Totally disconnected! Reattached and will give it a couple of days to ensure light stays off before I report back. We're a Honda, Ford, Subaru family and this is our first Toyota, so just starting to learn.

Thanks!

Your welcome
TS ROCKS!!!
Lots of great info here, and many people with a ton of knowledge.
Enjoy

troubbles · #7 (**permalink**) 04-28-2006, 11:02 AM

I also have a problem with a P0441 code on my 1998 camry I can clear it then it will come back in like 2 hours I cleared it and replaced the gas cap and it was gone for about 2 days then the check engine light came back on again. What more can I do.

mustang67408 · #8 (**permalink**) 04-28-2006, 11:21 AM

Quote:

Originally Posted by troubbles

I also have a problem with a P0441 code on my 1998 camry I can clear it then it will come back in like 2 hours I cleared it and replaced the gas cap and it was gone for about 2 days then the check engine light came back on again. What more can I do.

P0441 is usually not the gas cap.
P0441 is a small leak on the VENT side of the evap system.
Attched is 2 TSB's for a bad VSV, In my exp I personally would change the entire charcoal canister not just the VSV mentioned in the TSB. The charcoal canister comes with this VSV..
You need a TOYOTA scan tool to check all the pressure readings, so I wouls suggest a dealer or someone who knows how to diag this system.
There is also an overfill check valve in the fuel tank that is prone to cracking, it needs to be checked as well with a evap pressure tester.
Good luck