Help with engine light codes

I have a 2003 but this is for my friend with a 2000 2WD V-6

So far he has spent a fair amount of time and money trying to fix this.
Codes P0171 and P0441

So far had replaced.
Vapor cannister and everything that goes with that
New fuel pump
PCV valve & checked all vac lines.
O2 sensors.
Any other suggestions
Thanks

 

Stupid question, did you take the simple step of replacing the gas cap? And confirm he's closing the gas cap until it clicks once?

 

Yes, sorry did not list. That was the very first thing we tried a few months ago.

 

Purge valve at the engine. They also call it an EVAP VSV (vacuum switch valve)

 

Should look something like this, left side of engine bay I believe

Get the part number off the old one to make sure you get the right part

 

Same friends Tundra from couple months back ?

Codes P0171 and P0441 | Toyota Tundra Forum (tundras.com)

If so....mind answering a semi important question @shifty` asked in original thread ?

Also, don't want to assume wrongly but you are or have erased all codes properly ?

 

Did this on my honda element and it turned out to be the culprit. Evap canister box needed to be replaced eventually. Full of gas... Sold it before I had to deal with it

 

P0171 is an intake leak between MAF and plenum. Most likely an air tube with bends/folds in it, inspect carefully. Replace only with OEM stuff.

 

Yes same problem. Been awhile so started a new thread.
And all parts OEM ordered thru Coniceilli Toyota

Mechanics erased codes when parts put in and they come back on.
Thanks

 

Would that be the samething he also replaced. Called the
Valve Vacuum Switch
9091012268

Thanks

 

Probably. It should have a line going to it with a port with a green cap