The dreaded CEL - P0441 EVAP Vacuum switching valve etc
09-07-2006, 09:23 AM
#1
Registered User
Thread Starter
Join Date: Nov 2004
Posts: 798
Likes: 0
Received 0 Likes
on
0 Posts
The dreaded CEL - P0441 EVAP Vacuum switching valve etc
1997 4Runner 3.4 Liter 5 Speed SR5 4 wheel drive
So about a year ago it came on the P0441, we became good friends, got to know each other rather well, we would spend time at the beach together and sometimes I would be driving down the road and he would show up. The truck wreaked out the back, as did the charcoal canister itself, saturated with gas fumes....I flushed the canister out with soap and water believe it or not and the light went out for weeks, which was the longest stretch that it would stay out,,,turned out to be a temporary fix.
I replaced it.....no problem, light never came on...
Now a year later it did! I get the same code P0441....I have a connection so for the hell of it I throw in a new evap (again) got a sick deal so figure might as well just do it....
Light has been coming on again and did so every other day for the last couple weeks, then I realize I had the vacuum lines on the VSV hooked up wrong, so I change it back, and the light has been out for a week, longest time it had been out.
Well heading to work again, came back on! I did notice one vacuum line which had a sharp bend, perhaps even pinched so it would not flow.
I am definitely betting on a vacuum leak somewhere as another time I had the P0441 there was a MAJOR tear in a vac line.
So today at lunch I went to Advanced Auto Parts, bought some new vac line and ran a cleaner route with the line to avoid any and all pinches or sharp bends.
New gas cap, new evap with new vacuum valves etc,,,,,I am betting vac leak
Note to self always check the simple things first..
I welcome any insight
So about a year ago it came on the P0441, we became good friends, got to know each other rather well, we would spend time at the beach together and sometimes I would be driving down the road and he would show up. The truck wreaked out the back, as did the charcoal canister itself, saturated with gas fumes....I flushed the canister out with soap and water believe it or not and the light went out for weeks, which was the longest stretch that it would stay out,,,turned out to be a temporary fix.
I replaced it.....no problem, light never came on...
Now a year later it did! I get the same code P0441....I have a connection so for the hell of it I throw in a new evap (again) got a sick deal so figure might as well just do it....
Light has been coming on again and did so every other day for the last couple weeks, then I realize I had the vacuum lines on the VSV hooked up wrong, so I change it back, and the light has been out for a week, longest time it had been out.
Well heading to work again, came back on! I did notice one vacuum line which had a sharp bend, perhaps even pinched so it would not flow.
I am definitely betting on a vacuum leak somewhere as another time I had the P0441 there was a MAJOR tear in a vac line.
So today at lunch I went to Advanced Auto Parts, bought some new vac line and ran a cleaner route with the line to avoid any and all pinches or sharp bends.
New gas cap, new evap with new vacuum valves etc,,,,,I am betting vac leak
Note to self always check the simple things first..
I welcome any insight
09-07-2006, 01:27 PM
#2
Contributing Member
Join Date: Mar 2003
Location: Orange County, CA
Posts: 8,345
Likes: 0
Received 0 Likes
on
0 Posts
I have an ongoing issue with P0440, 441, and 446.
My truck has been running just fine so it's been just a matter of reset and move on.
I have noticed, though, that it only occurs within the first 10 miles with a cold engine and mostly on days when the humidity is a bit higher (happens more often with colder than warmer days, too).
My truck has been running just fine so it's been just a matter of reset and move on.
I have noticed, though, that it only occurs within the first 10 miles with a cold engine and mostly on days when the humidity is a bit higher (happens more often with colder than warmer days, too).
09-08-2006, 04:40 AM
#3
Registered User
Thread Starter
Join Date: Nov 2004
Posts: 798
Likes: 0
Received 0 Likes
on
0 Posts
I have an ongoing issue with P0440, 441, and 446.
My truck has been running just fine so it's been just a matter of reset and move on.
I have noticed, though, that it only occurs within the first 10 miles with a cold engine and mostly on days when the humidity is a bit higher (happens more often with colder than warmer days, too).
My truck has been running just fine so it's been just a matter of reset and move on.
I have noticed, though, that it only occurs within the first 10 miles with a cold engine and mostly on days when the humidity is a bit higher (happens more often with colder than warmer days, too).
maybe in certain conditions, slight vac leaks occur?
who knows,,,
09-12-2006, 09:46 AM
#4
Registered User
Join Date: Sep 2006
Location: New Mexico
Posts: 22
Likes: 0
Received 0 Likes
on
0 Posts
Maybe I can help with CEL P0441
Boston4runner and all, I just became a new member so bear with me on this long post. Thanks to all for these threads, I have solved several head scratchers:pat: using collective info from these forums and feel its time to contribute.
I’ve had the same P0441 CEL problem for a while and I’m pretty sure I’ve got it licked now. My years as a field helicopter mechanic have given me a few extra tools in my tool box…like logic. I know most of us are at home with fairly basic tools so sometimes you have to make due with what you have and keep it simple. Let me run a few things by you and see what you think.
1. I’ve read a lot of good advice about vacuum leaks, vacuum testers, starter fluid ect. I set my mind at ease about vacuum leaks by simply removing my tank filler cap an hour or so after driving. If you can hear an audible sucking sound when the cap is released, I think you can rule out a vacuum leak from the tank to the EVAP. If there was an open line, cut, crack, or bad cap, the pressure would have equalized shortly after you quit driving.
2. The VSV (Vacuum Switching Valve). My guess is this is the most common cause of the P0441 malfunction. If I read the trouble shooting chart right, you can get this fault when you have a loss of vacuum AND when vacuum is present and not supposed to be.
3. The VSV is a very simple on/off valve, it’s normally spring loaded closed, and electrically powered open. So using logic if you can blow air thru this valve with power/key off, the valve is bad or stuck. I’m old school, I just used my mouth.
4. To check the powered side of the VSV operation, here’s another helpful hint. The valve is 12VDC so you can simulate valve operation by hooking jumper wires from the valve directly to your car battery (obviously there would be a small spark so make sure your in a well ventilated area with no open fuel sources). I used covered alligator clips on 16-18 gauge wire. I’ve checked several Toyotas and the + (power) wire was always white with a red stripe. The ground is usually white with a green or blue stripe. Use the orientation of the plug to determine which pin in the switch is +/-. When you connect this final wire (complete the circuit) you should get an audible click and you should be able to blow through the VSV freely. Again, this is a very simple valve, you don’t even have to remove it to do this check. Don’t worry, I even hooked it up backwards just to see if it would damage it and it was fine (I have a spare valve).
Unfortunately, this valve (from my own experience) is prone to fail intermittently (like on a hot day) so you can’t rule it out even when it checks good once. This is probably why the light goes away for weeks at a time then comes on one sunny day. I suspect that the gate operation gets sticky from varnish in the fuel vapor. I found my original valve stuck wide open so I went to a wrecking yard and found a replacement. Here is another helpful hint. The part numbers change from model to model and year to year but it seems that it’s only the mounting bracket that varies. I was able to take a valve from a wrecked 2008 4Runner and install it on my 1997 T100 just by swapping out the rubber isolator bracket. The plug and line connections were the same. (wrecking yard valve $6.00, stiffing Toyota on an over priced $100 valve…Priceless)
Before I installed the wrecking yard valve, I put it through the electrical check I described above. It seemed a little weak and didn’t close tight so I rinsed the port out with WD40 and it perked right up with a nice audible click, snapping open and closing tightly. So then I decided to try this with my old valve (still stuck open) I sprayed lube in both ports and gently tapped it on the top and bottom till it started to close (yes I know what WD40 tastes like) then I applied power on and off and sprayed it again. After several cycles the valve was good as new so now I have two good valves and no check engine light.
I think I read that you or maybe someone else sprayed out the valve with carb cleaner. That’s probably not a bad idea to rinse out any varnish build up, but I would follow up with some WD40 to lubricate any dryness caused by the carb cleaner. I just used WD40 and it worked well.
I’m sorry to be so long winded but like you, I have had this problem for quite a while so I pass this on (in detail) hopping it helps you or someone else. At the very least it should help to eliminate some other possibilities.
I’ve had the same P0441 CEL problem for a while and I’m pretty sure I’ve got it licked now. My years as a field helicopter mechanic have given me a few extra tools in my tool box…like logic. I know most of us are at home with fairly basic tools so sometimes you have to make due with what you have and keep it simple. Let me run a few things by you and see what you think.
1. I’ve read a lot of good advice about vacuum leaks, vacuum testers, starter fluid ect. I set my mind at ease about vacuum leaks by simply removing my tank filler cap an hour or so after driving. If you can hear an audible sucking sound when the cap is released, I think you can rule out a vacuum leak from the tank to the EVAP. If there was an open line, cut, crack, or bad cap, the pressure would have equalized shortly after you quit driving.
2. The VSV (Vacuum Switching Valve). My guess is this is the most common cause of the P0441 malfunction. If I read the trouble shooting chart right, you can get this fault when you have a loss of vacuum AND when vacuum is present and not supposed to be.
3. The VSV is a very simple on/off valve, it’s normally spring loaded closed, and electrically powered open. So using logic if you can blow air thru this valve with power/key off, the valve is bad or stuck. I’m old school, I just used my mouth.
4. To check the powered side of the VSV operation, here’s another helpful hint. The valve is 12VDC so you can simulate valve operation by hooking jumper wires from the valve directly to your car battery (obviously there would be a small spark so make sure your in a well ventilated area with no open fuel sources). I used covered alligator clips on 16-18 gauge wire. I’ve checked several Toyotas and the + (power) wire was always white with a red stripe. The ground is usually white with a green or blue stripe. Use the orientation of the plug to determine which pin in the switch is +/-. When you connect this final wire (complete the circuit) you should get an audible click and you should be able to blow through the VSV freely. Again, this is a very simple valve, you don’t even have to remove it to do this check. Don’t worry, I even hooked it up backwards just to see if it would damage it and it was fine (I have a spare valve).
Unfortunately, this valve (from my own experience) is prone to fail intermittently (like on a hot day) so you can’t rule it out even when it checks good once. This is probably why the light goes away for weeks at a time then comes on one sunny day. I suspect that the gate operation gets sticky from varnish in the fuel vapor. I found my original valve stuck wide open so I went to a wrecking yard and found a replacement. Here is another helpful hint. The part numbers change from model to model and year to year but it seems that it’s only the mounting bracket that varies. I was able to take a valve from a wrecked 2008 4Runner and install it on my 1997 T100 just by swapping out the rubber isolator bracket. The plug and line connections were the same. (wrecking yard valve $6.00, stiffing Toyota on an over priced $100 valve…Priceless)
Before I installed the wrecking yard valve, I put it through the electrical check I described above. It seemed a little weak and didn’t close tight so I rinsed the port out with WD40 and it perked right up with a nice audible click, snapping open and closing tightly. So then I decided to try this with my old valve (still stuck open) I sprayed lube in both ports and gently tapped it on the top and bottom till it started to close (yes I know what WD40 tastes like) then I applied power on and off and sprayed it again. After several cycles the valve was good as new so now I have two good valves and no check engine light.
I think I read that you or maybe someone else sprayed out the valve with carb cleaner. That’s probably not a bad idea to rinse out any varnish build up, but I would follow up with some WD40 to lubricate any dryness caused by the carb cleaner. I just used WD40 and it worked well.
I’m sorry to be so long winded but like you, I have had this problem for quite a while so I pass this on (in detail) hopping it helps you or someone else. At the very least it should help to eliminate some other possibilities.
09-12-2006, 10:18 AM
#5
Contributing Member
Very good call on the advice T100.
I am battling something very similar on my Civic and I was starting to suspect the same thing was happening on these 4runners with continued P0441 codes because even after the charcoal canister is replaced, the code seems to mysteriously come back again. The system usually uses a vapor pressure sensor to monitor whether the charcoal canister is being evacuated and whether there is a positive or negative (vacuum) on the lines to indicate correct operation of the EVAP system. Very good info in your post!
09-14-2006, 10:01 AM
#6
Registered User
Join Date: Nov 2004
Posts: 196
Likes: 0
Received 0 Likes
on
0 Posts
thats what it was for me (VSV)...switched that lil' valve only....was cheap to do (never replaced the charcoal canister) and haven't got that code since!
they knew about it at my dealer (parts dept) too...so it seems pretty common.
Good advice T100!
-B
they knew about it at my dealer (parts dept) too...so it seems pretty common.
Good advice T100!
-B
Trending Topics
09-15-2006, 08:31 PM
#8
Registered User
Join Date: Sep 2006
Location: New Mexico
Posts: 22
Likes: 0
Received 0 Likes
on
0 Posts
Thanks all, one thing I forgot to mention is the other valve on the charcoal canister is a 5 VDC valve so make sure you don’t connect that one to the battery without a resistor to drop the voltage. I know what a pain this code can be. I was only able register my truck for one year because of this stupid code (New Mexico emissions rules). Anyway, I was only able to narrow this down because of the trial and error posts of others on this thread. My thanks to all who took the time to post their experiences.
09-16-2006, 06:06 AM
#9
Contributing Member
So which valve is which, I mean how do you tell the 12V one from the 5V one?
09-16-2006, 08:16 AM
#10
Registered User
Join Date: Sep 2006
Location: New Mexico
Posts: 22
Likes: 0
Received 0 Likes
on
0 Posts
I may have made a mistake. I rechecked the other valve and it says 12VDC also...(Loosing my mind). Anyway all the valves are marked with the operating voltage so you can verify before hooking them up. I snapped some photos to help Id the componets.
VSV installed
VSV removed
And here is the diagram that shows the valve marked "PWM-Vacuum"
Hope this helps
VSV installed
VSV removed
And here is the diagram that shows the valve marked "PWM-Vacuum"
Hope this helps
09-16-2006, 02:03 PM
#11
Contributing Member
Join Date: Oct 2005
Location: Smoky San Diego
Posts: 2,346
Likes: 0
Received 0 Likes
on
0 Posts
I have an ongoing issue with P0440, 441, and 446.
My truck has been running just fine so it's been just a matter of reset and move on.
I have noticed, though, that it only occurs within the first 10 miles with a cold engine and mostly on days when the humidity is a bit higher (happens more often with colder than warmer days, too).
My truck has been running just fine so it's been just a matter of reset and move on.
I have noticed, though, that it only occurs within the first 10 miles with a cold engine and mostly on days when the humidity is a bit higher (happens more often with colder than warmer days, too).
09-16-2006, 03:11 PM
#12
Contributing Member
Most relays (valves, switches, etc) will be 12V even though they are controlled by the ECU (most people assume 5V because the ECU runs at this lower voltage......often all the ECU does is to ground the power source on the device to complete the circuit). It is always good to verify operating voltage if it is so marked but I have used 12V on 5V relays and as long as you are brief (ie just long enough to hear a click) then you will usually not damage the device (you can also use a 6V battery to test 5V items without issue).
Last edited by MTL_4runner; 09-16-2006 at 03:13 PM.
08-23-2014, 01:02 PM
#14
Registered User
Join Date: Aug 2014
Posts: 1
Likes: 0
Received 0 Likes
on
0 Posts
p0441 and hot restarting difficulty
Had reoccurring p0441 and truck took several cranks to start when hot. The charcoal canister installed by previous owner turned out to be installed incorrectly. The two larger hoses on canister were routed to engine wrong. Switched them and no more cel or starting trouble. The hose closest to the front of the truck SHOULD be routed to the vacuum line on top of the engine, NOT the vsv, as mine was. Maybe others have this issue, too? Easy fix!
2001 tundra access cab
V-8
4x4
Sr5
2001 tundra access cab
V-8
4x4
Sr5
04-17-2016, 03:18 AM
#17
Registered User
So my 1995.5 2rz had the P0441. Checked the VSV with 12VDC jumpers and it checked out fine. I clicked each time voltage was applied. Code kept coming back. Replaced the gas cap and the vacuum hose coming out of the carbon canister. Code came back. Finally just replaced the VSV. Done. No code. It's a cheap part for $27 on Amazon. Dorman 908-611 I think. On Amazon it says it DOESN'T fit my truck but it's a perfect fit.
So just because 12VDC applied to the VSV makes it click does not mean that it isn't the problem. Not sure why it doesn't work when plugged in to the truck. Maybe 5VDC is not enough to operate a faulty one but 12VDC is.
Just my thoughts on troubleshooting here. Good luck.
So just because 12VDC applied to the VSV makes it click does not mean that it isn't the problem. Not sure why it doesn't work when plugged in to the truck. Maybe 5VDC is not enough to operate a faulty one but 12VDC is.
Just my thoughts on troubleshooting here. Good luck.
09-12-2016, 07:23 PM
#18
Registered User
Join Date: Apr 2016
Posts: 1
Likes: 0
Received 0 Likes
on
0 Posts
Do you need the vsv on a 97 3.4
I've done a 3.4 swap on my 85 pickup and me and my buddy did all the work and wiring. But I don't have the charcoal canister. So my question is what do I do with the vsv? Do I even need them?
Thread
Thread Starter
Forum
Replies
Last Post
