P0446
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From: SW Va
Its a vapor recovery system vent malfunction code. Maybe look to the solenoid, or its electrical connections. Not sure just where its located on your year/model, look in your repair manual, if you don't have one the AutoZone site might have a location in their repair section.
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Fleet Owner
Joined: May 2009
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From: Gilbert, PA
Set the light again.
It has the P0446 and P0455
What else should I be looking at. I dont have access to a smoke machine.
I pressurrized the system the best i could and sprayed the lines down with soapy water. No leaks that I could see
It has the P0446 and P0455
What else should I be looking at. I dont have access to a smoke machine.
I pressurrized the system the best i could and sprayed the lines down with soapy water. No leaks that I could see
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From: SW Va
Have a read here on this TSB. http://www.stangnet.com/images/stori...s/03-20-03.pdf EDIT: BW did you remember to tighten the gas cap & or check its gasket to make sure it isn't damaged???? The system thinks there is a leak somewhere, cap, hose, vent not closing, wiring problem to the vent, preventing the computer close signal from reaching it, or even a computer problem
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From: SW Va
Here is some more reading fwiw on the two codes that might ring a bell, but they sorta say the same thing as the above TSB link
P0446 Evaporative Emission Control System Incorrect Purge Flow OBD-II Trouble Code: P0455 Evaporative Emission Control System Leak Detected (no purge flow or large leak) We are to work the lowest number trouble code first, so the hints for the P0446 code would take precedence in your trouble shoot.
P0446 Evaporative Emission Control System Incorrect Purge Flow OBD-II Trouble Code: P0455 Evaporative Emission Control System Leak Detected (no purge flow or large leak) We are to work the lowest number trouble code first, so the hints for the P0446 code would take precedence in your trouble shoot.
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Fleet Owner
Joined: May 2009
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From: Gilbert, PA
Got new used solenoid up by engine today. That didn't fix it either.
My gas filler neck is stainless(factory), so I am doubting and rust there.
I have a "tick" coming from the engine, I am wondering if that has anything to do with it
My gas filler neck is stainless(factory), so I am doubting and rust there.
I have a "tick" coming from the engine, I am wondering if that has anything to do with it
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Joined: Jan 2004
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From: SW Va
The computer is saying something is wrong with the vent solenoid circuit & that it is sensing a large vacuum leak. So from that to me it suggests that something electrical is wrong with the wiring to the vent solenoid, the solenoid itself, like its open all the time, maybe defective, or maybe not recieveng voltage from the computer to cause it to close because of a wiring problem, or maybe the computer has a problem creating or sending the close signal. Anyway at this point I'd not be inclined to go off on an engine tic/noise tangent & stay focused on what the trouble code suggests to look for. You say all of the hoses, fill tube & gas cap physically look ok, you havent reported smelling gas fumes, or hearing vacuum leak sounds, so that sorta narrows things down to the electricals operating the vent solenoid.
Keep us posted on your trouble shoot.
Keep us posted on your trouble shoot.
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Fleet Owner
Joined: May 2009
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From: Gilbert, PA
Any idea on on how to try and activate the solenoids, to check for power? My scanner only goes to 99 so it is not much help.
Does anyone know if I can get a cartage for my snap on MT2500 to go up to 04?
Does anyone know if I can get a cartage for my snap on MT2500 to go up to 04?
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From: SW Va
Hook your multimeter up to the vent solenoid & on a cold engine, have your helper turn the ignition switch to KOEO & see if the computer generated signal is getting to the vent solenoid. If not, work your way forward, checking wiring & connectors as you go & work your way all the way back to the firewall mounted computer electrical connector. If no vent solenoid voltage there, look to a connector pin/socket or computer problem. OR, you could cut to the chase & just back probe that connection first & work your way rearward!!!!
EDIT: Review the P0446 link in post 7, for whats likely wrong. At KOEO the ECM supplies B+ to the vent solenoid & the ECM ground switches the solenoid to cause it to operate. So if the B+ lead to the vent solenoid, or its ground wire back to the computer are corrupt, the solenoid isn't going to close, thus the system is gonna detect a big vacuum leak & the ECM is gonna get upset!!!!
EDIT: Review the P0446 link in post 7, for whats likely wrong. At KOEO the ECM supplies B+ to the vent solenoid & the ECM ground switches the solenoid to cause it to operate. So if the B+ lead to the vent solenoid, or its ground wire back to the computer are corrupt, the solenoid isn't going to close, thus the system is gonna detect a big vacuum leak & the ECM is gonna get upset!!!!
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Fleet Owner
Joined: May 2009
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From: Gilbert, PA
Which is the vent solenoid? The one on the charcoal canister(by spare tires) or the one up by the engine?
So the solenoid will cycle when the key is just turned on? How long will it stay on for?
So the solenoid will cycle when the key is just turned on? How long will it stay on for?
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From: SW Va
The engine bay solenoid is called the charcoal canister purge valve. It's job is to open when we crank the engine for a cold start, so engine vacuum can suck the stored gas fumes out of the charcoal canister. Because the gas is already in vapor form, it'll ignite easier in the cylinder & thus give us faster cold starts.
The solenoid on the tank end is called the vent, its supposed to operate when we start the engine, so if you don't have a multimeter to test its coil to make sure it has continuity/not open circuit, or to see if the computer supplied B+ is reaching it at its electrical connector, or if the computers ground switching driver is ground switching the solenoids electrical load, so it'll close, listen to, or feel it when your helper goes to KOEO, to see if you can determine if its working. if its not working, then you'll have to begin a visable wiring inspection & or some voltage back probe testing as suggested above, to see whats going missing & where the problem is.
The solenoid on the tank end is called the vent, its supposed to operate when we start the engine, so if you don't have a multimeter to test its coil to make sure it has continuity/not open circuit, or to see if the computer supplied B+ is reaching it at its electrical connector, or if the computers ground switching driver is ground switching the solenoids electrical load, so it'll close, listen to, or feel it when your helper goes to KOEO, to see if you can determine if its working. if its not working, then you'll have to begin a visable wiring inspection & or some voltage back probe testing as suggested above, to see whats going missing & where the problem is.
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Fleet Owner
Joined: May 2009
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From: Gilbert, PA
I used a 12v drill battery to "activate" the solenoid on the vent. I could hear it doing something. I can do the same to the purge valve.
Then I will have to check for battery voltage at the plug for each
Then I will have to check for battery voltage at the plug for each
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From: SW Va
Another thought, if you don't have or can't come by a multimeter for some electrical testing, you could use a 12 volt test lamp, or rig one with some wire & a small lamp, or 12 volt LED, to test for power, or ground switching.