2018 GX460 Wont Start after Fillup (1 Viewer)

[Surrendered]

3 months ago started getting p2441, p0441. So replaced gas cap. Cleaned MAF sensor. Codes came back. Replaced MAF. P2441 did not come back.

2 months ago
After complete fill of tank GX won't start. Must remove gas cap. Wait a few minutes. It starts but struggles. Insert gas cap. No troubles unti next fill up.

started getting p0455 with p0441. Did smoke test.
Did not see smoke. Using xTool tested evap and pressure was consistently 95 to 99 kPa. Manually Tested valve assembly switch, canister purge switch. Believed canister switch was weak and not closing completely. Replaced entire canister that came with new switch.

Within a week Codes came back. Did another smoke test. This time smoke came from back of filler neck. Last week replaced filler neck with new.

Today only filled to 3/4 and struggled but did start.

Using xtool retested evap. Pressure started and ended at 14.151 kPa. Appears I fixed the leak.

Over last 2 months have replaced the following with new toyota parts:

• Gas cap
• Charcoal canister
• Fuel filler neck assembly

Any ideas on why I continue to get p0441 & p0455, and why it struggles to start after adding fuel to tank?

 

[emblu.denslob]

Full disclosure - I'm not positive on this.......
From what I've read/heard(on other vehicles) the issue might be with the valve assembly vacuum switch. Others call this a Vapor purge Valve.

I'd think a dealer might know this but that could end up costing $$$.

 

[r2m]

Having a gas cap off will trigger a code. But other than that, I have no idea what your issues could be.

 

[Hehena]

Has the fuel pump recall been done?

 

[Pennwestmechanic]

I read one story that the purge vacuum lines were incorrectly attached after being repaired or replaced. You'd only know this at your next fill up.

Maybe you can get a schematic of the evap system?

 

[Surrendered]

I missed the fuel pump "Not Recall". Thanks for mentioning this Hehena. For anyone else having similar issues check out the Lexus Customer Support Program 23LE01 or 23LE02.

https://www.nhtsa.gov/?nhtsaId=10235219

https://www.nhtsa.gov/?nhtsaId=10235220

I will be scheduling an appointment and allowing dealership to fix this one for me. Hopefully for free or almost free.

Thanks to all who replied to my question.

 

[Surrendered]

Follow-up
The fuel pump was not the issue. Dealership will not replace fuel pump unless codes match the ones on the CSP. So, even though the Valve Assembly Vacuum Switch #1 and 2nd VAVS tested successful previously; the dealership recommended changing both. I ordered the parts and swapped both of them. My issue is now resolved.
Part numbers 25860-0S020 and 25860-0S010.