BOSTON4RUNNER

hello,

Had the code P0441 I think it is on a 1997 3.4 liter 4 Runner SR5

for the vacuum switching valve, I put in a new one and it seems to constantly tick when running, I never noticed this before with the other one, perhaps because it was bad

light was out for quite a few days as I disconnected the battery, reset computer

anyway today the light came back on, I opened the hood and could not hear or feel any ticking, switching at the valve like I did the other day when I installed it

anyway, I then physically moved the valve itself, wiggled it, right away starting ticking/switching again like it did the other day....perhaps I have a bad connection and it stopped ticking this morning and set off the engine light? do these work consistently while running, or intermittently? maybe jsut a coincidence that it started working when I touched it?

please advise!

thanks, tim
boston ma

MTL_4runner

Keeping in mind that P0441 says "Pressure in charcoal canister does not drop during purge control" and "During purge cut-off, pressure in charcoal canister is very low compared to atmospheric pressure".

If you already replaced the VSV then there are really only 2 other options left:
1) Even though you checked, there is still is a vacum leak in one of the lines
2) The EVAP canister might need to be replaced

BOSTON4RUNNER

I will check the vacuum lines

I am also using a better diagnostic tool that I have here at work

I am a marketing director at a transit authority, and they have some sick fun toys in our bus garage so I am going over in a minute

I guess the usual starting fluid check for vacuum leaks will suffice?

thanks again for the help

also dare I ask how much a canister goes for?

MTL_4runner

A canister is not cheap at all (in the hundreds $$$$).....try to get a used one if possible.

I would use a hand actuated vacum pump to check for leaks on each line (they are cheap if you don't own one).

BOSTON4RUNNER

first things first, tonight will pull codes right after work, then check vacuum

maybe I can find a used canister...

4Crawler

iTrader: (3)

Clean the charcoal cannister. Just need some low pressure conpressed air (about 40 psi) and the instructions in the Factory Service Manual.

BOSTON4RUNNER

I will do that

tonight I am clamping all the vacuum lines, a couple of them in the area of the VSV valve do seem a little loose fitting

I pulled the code, it said P0441 B...is the B part of this code? I am also going to check out the area near the gas, tank, filler neck etc, I hear that a vacuum leak in that area can also cause these codes?

thanks again

tim

BOSTON4RUNNER

just checked all vacuum lines in engine compartment, used soapy water and also starting fluid

i could not find any leaks

also blew very light air through the charcoal canister, does not seem to be any leaks in that either

MTL_4runner

You can use the smaller zipties to secure the ends of the hoses once they check out ok to ensure a good seal for vacuum.

Even though this is for a 2003, the system is still almost the same:
http://www.tankota.net/repair/Repair...e/cip0441p.pdf

Most of the time when the VSV is bad it will throw both P0441 AND P0446.
When a vacuum leak is present, you will likely just see a P0441 OR P0446 (may be some exceptions).

You really should get a handheld vacuum pump or at least a vacuum guage to be able to diagnose the problem properly.

BOSTON4RUNNER

i will get a pump and gauge, before going any further

any links to what type of pump i should get?

thanks again

MTL_4runner

You can get a vacuum pump like the one that comes with a brake bleeder:


or at least a simple guage like this:

BADLNDS

heres a TSB fix for that problem...hope this helps. I was told the same...start with the VSV valve...then the tubing and lastly the charcoal canister (cause thats the most expensive)

-B

BOSTON4RUNNER

badlands

did you find the source of your problem?

if so what was it?

BADLNDS

my light stayed off for 3 weeks and then came on again on a hot humid day...I am replacing the VSV valve first next week...I'll keep you posted.

BADLNDS

I was trying the not to top off the fuel to see if it was that...I was also told to replace the rubber seal on the gas cap...so i am replacing seal along with VSV valve....that tsb is the repair for that condition...so i will do step at a time...and if all fails...i'll change the canister last (I hope it doesn't go that far?)

-B

BOSTON4RUNNER

im gonna replace the vacuum lines, will likely do this tonight, then will check for vacuum leaks once again as MTL has suggested

if that doesnt do it

i am, maybe i shouldnt but before replacing the canister

i am going to take it out, give it a real hot bath in hot water with palmolive, flush it all out, blow it out with light pressure air

hang it out to dry, i also wonder if there is a spot to drill a drain hole then repair it with body panel adhesive or similar

then re-install it

i have done the same to standard transmissions that were not shifting right, and people would cringe, would re-install throw in synthetic and never had a problem

BOSTON4RUNNER

replaced vacuum lines,,,,and today light came back on

man o man this is going to drive me nuts!

I hope the bath I give the canister will work, but still have to check with a vacuum gauge and pump before I do that...

MTL_4runner

For the EVAP canister you could try drilling a hole near the bottom and let it drain out any gas that might be in there and then use a self-tapping oil pan bolt with a rubber washer (only do it hand tight with a socket....no ratchet!). There could be 2 complications I can think of when doing this. First, I have no idea how thin the plastic is in this area and where to drill because there might be some structural areas on the canister. Second, you never know how brittle the plastic is or has become over time and it may shatter if you are not careful. Also remember the canister is not empty (usually filled with activated charcoal, but may be another substance which absorbs gas vapors) so whatever material is inside may come pouring out if not careful.

You might also want to take a look at this:
http://aftermarketbusiness.com/after....jsp?id=164723

BOSTON4RUNNER

hey

thanks again for all your help

first i will use the vacuum gauge and pump

check it out

then a very careful drill clean and drain may be in order

i will let you all know how i make out

BADLNDS

That was a good article MTL 4runner!

boston..let me know how you made out...I'll keep you posted on my repair. And if you find a way to fix the canister instead of replace it...let me know.

-B