I am new to the speaktoyota forum, but this is my fourth Toyota. I have a 2009 Venza with 45k miles. After filling up, I noticed it threw P0171, P0441, and P0455 codes. I replaced the gas cap, but it didn’t fix the issue. When I stop to refuel, the car struggles to start.
Now, I leave the car running while fueling, but it stalled the last time. Could this be an issue with the evap purge valve?
P0171 points to a lean mixture, possibly due to excess air in the mix. This could be caused by a cracked air hose between the MAF and the plenum especially in the ribbed sections. The hose might look fine when the engine is off or idling, but under load, engine movement could open a small crack, allowing extra air in.
For the other two codes, a smoke test is the best way to pinpoint the source of the leak.
I noticed that the faulty evaporative purge valve is drawing in fuel vapor right after refueling, which makes it hard to start the car. This might also be causing the other codes. Please keep me updated on the progress.
Thanks. I’ve been seeing the same thing in my research. I’ll replace the part tonight.