P0446 has nothing to do with the canistor !
DTC P0446 Evaporative Emission (EVAP) Vent System Performance
This DTC tests the evaporative emission (EVAP) system for a restricted or blocked EVAP vent path. The control module commands the EVAP canister purge solenoid valve Open and the EVAP canister vent solenoid valve Closed. This allows vacuum to be applied to the EVAP system. Once a calibrated vacuum level has been reached, the control module commands the EVAP canister purge solenoid valve Closed and the EVAP canister vent solenoid valve Open. The control module monitors the fuel tank pressure (FTP) sensor for a decrease in vacuum. If the vacuum does not decrease to near 0 inches H2O in a calibrated time, this DTC sets.
DTC P0452 Fuel Tank Pressure (FTP) Sensor Circuit Low Voltage
How to troubleshoot an EVAP Pressure Sensor problem P0452 GMEVAP Vent Solenoid Code P0446 The solenoid is stuck open !
replace the switch under the automatic buttons. 52 dollar fix instead of 400 dollars at dealer! most of the time due to solder breaking in switch! order online pop dash off replace. no tools needed
ur acuator doors are bad usually happens when battery goes bad or is unhooked google sparkys answers and theres how to and pictures thats how i fixed my 03 1500hd also until i found out how to fix id go to the fuse box under hood while truck was on and pull ac fuse wait 10 sec replace and it usually blow out front vents until i turned truck off if u recently had battery go bad or unhooked look at recalibration on sparkys answers its simple and might be all u need
Seems to be a faulty solenoid in the gearbox system by the sound of what you have explained. That could trigger a check engine light sometimes, please confirm if this is the case. I assume it is a electronic gear box system here and hence this is a common problem from what you have explained. If you have any question please do not hesitate to ask, I may take some time to answer but I will get back to you. Hope this helps.
you cannot its that simple i do think you have been watching to much CSI ,their is shrouds all around the lock rendering it impossible ,what i do here is wind a back window down if their manual with a coat hanger to pull up and piece of concrete re-inforcing rod to push down
The proper way to determine what's going on in your engine is to install a temporary (or permanent) mechanical gauge. (yours is electro -mechanical) your oil pressure changes with engine rpm but at idle, it should not drop below 15psi (I don't accept less than 20). The gauge and light is set to come on at a pressure that is just a bit higher than the max low pressure so you have a chance to correct the cause without destroying the engine. (though sometimes even that repair can be expensive). Since the gauge setup or having someone put a gauge on there costs more than a new sending unit for your current arrangement, I'd suggest you replace the sender and if you see identical readings, then you need to have the oil pan removed and the crankshaft bearings and oil pump looked at. Doing nothing can cost you an engine.
Your either not going to believe this or hate me for it. Your ECM has a "cold start" circuit with a special set of commands to start the car when cold. It might have lost the command to fire the coil.
