Majindan
New member
Yeah so, what I've done thus far:
Replaced several vacuum lines around the engine, OEM PVC valve replaced, properly cleaned MAF, LTFT doesn't go beyond +6 per Torque Pro, double checked vacuum lines that could be reached while replacing as noted above. New OEM gas cap, no apparent breach around filler neck, although I do smell gas at times when the truck bakes in the sun, cleaned metal lip that cap screws onto as well.
Evap tests won't clear readiness test in Torque either. Had a similar issue about this time last year and after sealing an air leak around the molding of the sound resonator box (or whatever it's called) the evap test cleared and I got through emissions. Worth mentioning the VSC off light only comes on every other time I start the truck, although the CEL just burns steady regardless, no other dash lights/warning lights are on. Maybe worth mentioning is that even if the VSC off light is not on, I've lost traction control outside of 4WD/AWD modes, I can fishtail on wet roads all day right now.
I don't have the cash to take it to Toyota for a "proper test" so I am hoping there is something I can test DIY style without just throwing new parts at these codes.
Yes, I've read through multiple other posts regarding these codes, just haven't seen one with sometimes on, sometimes off VSC off warning in conjunction with these two codes. Typically I'll reset the CEL, and about the second tank in, the CEL comes back with just the P0440...about 4 tanks more, it's buddy P0446 is added in.
2002 SR5 4WD, 177k miles, and I always use OEM/Denso parts for everything. 4WD engages fine, no other real mechanical issues.
Replaced several vacuum lines around the engine, OEM PVC valve replaced, properly cleaned MAF, LTFT doesn't go beyond +6 per Torque Pro, double checked vacuum lines that could be reached while replacing as noted above. New OEM gas cap, no apparent breach around filler neck, although I do smell gas at times when the truck bakes in the sun, cleaned metal lip that cap screws onto as well.
Evap tests won't clear readiness test in Torque either. Had a similar issue about this time last year and after sealing an air leak around the molding of the sound resonator box (or whatever it's called) the evap test cleared and I got through emissions. Worth mentioning the VSC off light only comes on every other time I start the truck, although the CEL just burns steady regardless, no other dash lights/warning lights are on. Maybe worth mentioning is that even if the VSC off light is not on, I've lost traction control outside of 4WD/AWD modes, I can fishtail on wet roads all day right now.
I don't have the cash to take it to Toyota for a "proper test" so I am hoping there is something I can test DIY style without just throwing new parts at these codes.
Yes, I've read through multiple other posts regarding these codes, just haven't seen one with sometimes on, sometimes off VSC off warning in conjunction with these two codes. Typically I'll reset the CEL, and about the second tank in, the CEL comes back with just the P0440...about 4 tanks more, it's buddy P0446 is added in.
2002 SR5 4WD, 177k miles, and I always use OEM/Denso parts for everything. 4WD engages fine, no other real mechanical issues.
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