DRACO A5OG

I have been chasing down this moronic error code and found allot of mis-directs and wrong fixes. I figured I will post my findings and hope it will help others.

Issue: Error Code P0441, EVAP Emission Control System PURGE FLOW FAULT.

So almost everywhere I searched, watched and read stated it is the VSV. True but according to Haynes it is the TVV. What ever the fudge it is called it is the 3 Way Vacuum Switch Solenoid located on top of the Charcoal Canister, in my Gen in the engine bay, with the blue connector. Toyota Part# 90910-12109 Great! ( But wait, when one does a part search this part is not replaceable and is for 97-2000, WTF??? )

I was watching a fella on youtube and he found his fault on the vacuum hose connector going into the throttle body. DING DING DING. ( will come back to this )

Diagnosis:

TVV aka VSV at the Charcoal Canister. Used a 9 volt battery to activate the switch and blew air thru all ports, PASS

Checked the connector from the ECU, car in ON position, 12.4 volts, PASS

Pressure Sensor, two sensor connectors both read 5 volts, PASS

Hoses, all clear to the second VSV on the fuel rail. 9V Volt Test, PASS

Hoses to the throttle body was hard and cracked. BINGO, vacuum leak. Replaced with 5/16 Vacuum Hoses.

Here are some videos of my diagnosis:






Please forgive me I am just a lowly DIYer. :-(

DRACO A5OG

Update: Confirmed, Vacuum Line to Throttle body was leaking like crazy.

Reset CEL. We shall see :-)

LeX2K

Excellent bit of work I must say. Hope the problem stays fixed.

DRACO A5OG

Oh geeze, thanks. Yeah. I hate to give up but checking the lines was a big shocker how bad they were. Literally crumbling and snapping off.

Showed my wife, she did not believe me until she heard the massive air leak. I love YouTube!

mhusted318

I have a 96 Es and I'm only getting a p0446. I noticed that every time i search for that code I come up with a p0441 and a p0446. You think I should check the same thing?

DRACO A5OG

What was the code reader description?

Update: Son has been driving around for last couple of days and no CEL and he thinks it drives better 😝

mhusted318

I think it was a evap circuit malfunction or something. I'm going to test the VSV. I remembered back in the day when I worked for advanced auto parts one of my managers and I were dealing with a guy with a Camry who needed a VSV and my boss looked At me and said "those stupid ****ing things always go bad." Excuse my language lol

DRACO A5OG

Well, in that case, it could be the VSV on the Charcoal Canister side or the Vacuum Canister side which is below the battery tray.

Just get a fresh 9 volt battery ( a less than 9 volt is not powerful enough to trip the VSVs ) a piece of long enough hose and blow thru it while tripping the VSV. Find the port that will not pass air, trigger the VSV. DO NOT USE COMPRESSED AIR on the Vacuum Canister or you will get this:



I would also check the connectors with Digital Volt Meter, Remember put the ground lead on the engine block or known good ground. DO NOT PUT Both leads into the connector, it will fry the ECU.

While you are at it, look for loose or cracked hoses. Be very careful with the hard ones they will crumble on you or worse break the VSV ports, they are very very brittle. See last Video, this was off my Vacuum Canister:

This pic was from the Vacuum Canister to the fuel rail VSV's



Jim

DRACO A5OG

Son reports no CEL :-)

mhusted318

I just got done at advance couldn't find any indication as to wether the canister and VSV were under the hood or by the tank. I've seen it both ways during googling. Fortunately I found out all my evap stuff and lines are between the air box and booster. I traced all the lines to make sure all the lines were good. And I quickly found out one of them was cracked and it appeared like it happened before. As there were hose clamp markings closer to the end of the hose. Picture for reference. Going to clear light and see what happens

DRACO A5OG

Oh yeah, that will throw a CEL.

check the other lines under the cover and going out to the throttle body, feel under neath or use a mirror, you may be surprised. those hoses are not supposed to be hard but pliable

DRACO A5OG

Update: 10 days later still no CEL and car drives smoothly per my son

DRACO A5OG

Update: 2016, no P0441 culprit leaking vacuum hose on Throttle Body.