No Leaks detected from smoke tester
Tested all solenoids via bi directional controls can hear an audible click from all of them... Purge valve is being duty cycled when controlled smoke tester did not detect a leak found a loose vacuum line from intake to purge valve replaced with new line. Found an aftermarket gas cap previously installed checked with grease seems to be sealing well. Looking for a new direction thanks
Take a real close look for a rusted fill pipe smoke does not show from the rusty spots try to pressurize system with smoke machine and try some soapy solution
The code for incorrect purge flow could be caused by the purge solenoid not sealing and leaking vacuum or not opening allowing vacuum to flow through. Check the solenoid for leaking vacuum or not opening. Also look at the fuel tank pressure sensor reading. Make sure it is reading correctly with the fuel tank cap off
I had an Escalade like that. I assumed that it was a sticking vent or purge valve. Replaced both and no come back yet.
Check the vent solenoid more than once! Like maybe 15 times in under a minute. I have found that they will pass 8 or 9 tests, then leak after about 10 or 12 activation cycles.
I’ve done a ton of evap canisters but start with factory cap always, then proceed with testing that evap purge solenoid until it fails like others stated that is also my experience with those just cause you hear a click doesn’t confirm much you must test it like the system does . Use a vacuum pump and check it for decay over time while activating solenoid
Make sure the purge is not leaking vacuum to the tank and that your fuel tank pressure sensor is reading correctly. You can have no leak and a skewed FTP sensor. Also see how quickly it dumps tank vacuum when commanded off. A slow bleed can indicate a restricted canister or vent.
You are fortunate to have the 446 circuit code. Most Toyota's don't get past the vague and all inclusive 440 performance code, then when they do, 441 is not much more helpful. They always seem to not leak either, and turn into a process of elimination, until the ultimate decision to replace the entire canister and related solenoids that come with it is made with very little confidence. At least…
I've been kicked around a few times with those older Toyota evap systems. Seems like they do not follow the traditional design/operation as expected from typical evap systems of that era. I reference the youtube video by Wells manufacturing from 2017 to help you understand how they operated. youtube.com/watch?v=BkxeXZ…
i would check the evap purge valve just blow and apply vacuum on both side of the valve i had them leaking on on one direction i do smog in California i see lots of them if the valve is ok and you have no leak fuel pressure sensor should read 0 inch on see level after semoving the gas cap i have seen evaporations can vent valve ground wire by the valve deteriorated and the valve still working
Two things to keep in mind. Using a scan tool to operate the evap solenoids doesn't mean they are working correctly just because you hear a clicking. You need to look at your flow meter to determine if you have a leak. Secondly, depending on the amount of fuel and the capacity of the canister, you may not see any smoke. Make sure you use CO2 and a detector when looking for leaks. I always seal…