P0446 Code

FrankB43015 · 02-20-2014, 06:04 PM

I recently purchased a 2009 Avalanche. The check engine light came on and I had it checked. The reader showed P0446 - Evaparator Solenoid. I replaced the solenoid and the light stayed on. Reset the light and 24 hours later it was back on. Reset the light again and it's back on again. Replaced the new solenoid and the light is back on. Any thoughts from the experts?

autojoe · 02-20-2014, 07:28 PM

5.3 or 6.0?what solenoid did you replace?vent solenoid?do you have battery voltage to solenoid?

FrankB43015 · 02-25-2014, 02:15 PM

I have the 5.3. I checked with the motor not running, but the key on and have 9.5 volts to the evaporator solenoid.

j cAT · 02-25-2014, 02:53 PM

Quote:

Originally Posted by FrankB43015

I recently purchased a 2009 Avalanche. The check engine light came on and I had it checked. The reader showed P0446 - Evaparator Solenoid. I replaced the solenoid and the light stayed on. Reset the light and 24 hours later it was back on. Reset the light again and it's back on again. Replaced the new solenoid and the light is back on. Any thoughts from the experts?

with the older vehicles I would guess you have a canister problem or perhaps a small leak. since you have a 2009 these are with defective in fuel tank pressure sensors.. go check this out .. do search and call a few dealers ... get TSB on your vehicle ..

this code is from the PCM commanding a evap fuel system test. the test that your vehicle failed on it the vacuum decay is not correct... the in the fuel tank ,, pressure transducer measures this decay so since it is a 2009 I guess it is this transducer...

on the older pre 2008 vehicles this can be a vent valve/bad fuel cap/leak at the fill neck/canister defective and other items...with just this 446 again this should be that GM DEFECTIVE PRESSURE transducer sensor.

good luck ...most techs don't know much about this stuff too technical...

FrankB43015 · 03-12-2014, 07:57 PM

Well... I'm not sure what happened, but the PO446 has cleared and a PO449 has appeared. The new canister and filter should arrive any day now. Thanks for the help.

j cAT · 03-13-2014, 07:55 AM

Quote:

Originally Posted by FrankB43015

Well... I'm not sure what happened, but the PO446 has cleared and a PO449 has appeared. The new canister and filter should arrive any day now. Thanks for the help.

report what happens after the canister replacing... also I hope you avoid over filling the fuel tank.. fill up then do your driving. do not fill up then allow the vehicle to not run especially if you park in a heated garage etc..

FrankB43015 · 03-13-2014, 03:13 PM

I'm afraid I'm guilty of both counts. I fill up on my way home and I fill until I hit the next whole dollar.

The canister came today. I plan on replacing it this weekend. I'll now buy my gas on the way to work... at least two gallons will be used by the time I park it.

j cAT · 03-13-2014, 05:31 PM

Quote:

Originally Posted by FrankB43015

I'm afraid I'm guilty of both counts. I fill up on my way home and I fill until I hit the next whole dollar.

The canister came today. I plan on replacing it this weekend. I'll now buy my gas on the way to work... at least two gallons will be used by the time I park it.

sounds good

post back after some time passes after your canister replacing... also make sure those lines are clean. if you see black goo in them you will need to wash them out or replace..

FrankB43015 · 03-18-2014, 07:16 PM

Its finally in, the code cleared. On the Avalanche you do have to drop the spare tire. I replaced the hose. I couldn't find the vent filter though... not sure whats up with that but its not easy for a fatboy to roll around on the floor looking for this stuff either. Thanks everyone for your help.

ricediana64 · 03-18-2014, 10:42 PM

I imagine the inline fuse could also be blown.

j cAT · 03-19-2014, 05:49 PM

Quote:

Originally Posted by FrankB43015

Its finally in, the code cleared. On the Avalanche you do have to drop the spare tire. I replaced the hose. I couldn't find the vent filter though... not sure whats up with that but its not easy for a fatboy to roll around on the floor looking for this stuff either. Thanks everyone for your help.

so the canister did it ... don't over fill that fuel tank...

if the dealership did this repair god knows what else they would have broken to jack up the cost and increase the service managers take ..

loose some weight ..too much is not good for you...eat good food , low carbs diet.

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