Found this rubber tube dry rotted while looking for a vacuum leak due to p0171 and p0174 code on a 2001 f150 4.2 4x4. This is from the down tube from the vapor management value going to the tank canister (I think). The picture of the rubber tube is from the driver's front wheel well. Looking for a part number as the local auto parts shop didnt have a clue what was Im looking for.

Thank you!

 

That's not a vacuum hose...it's the line that goes back to your charcoal canisters I believe...basically just replace it with something rated for fuel...AutoZone has a secret world (kinda like Narnia or Hogwarts) if you're cool with them (or you can talk them into showing you the hose by the foot section) where they can take you to look through fuel and heater hoses for what you're looking for. Just match it up and cut off a piece or three...get extra if you like, it's fairly cheap.

Unfortunately, it's not the cause of your codes...keep looking.
If it were you'd have codes for evap...I think...forgot what those codes were but I'm pretty sure you just have a vacuum leak.

 

If you’re looking for a cure for those two codes for a 4.2, just do the intake manifold gasket and isolator bolts. Especially if never done.

It’s a 4.2 owner rite of passage.

 

If the tube does not have a hole in it it's not going to be the source of your problem. But if you want to replace it just take the hose to the auto parts store and get a similar piece. It's so short that a piece of heater hose would do the job.

If you want to narrow down the source of your codes get a scanner with live data ability. And/or freeze frame. See what the conditions are when the code was set.

p.s. another source of vacuum leaks is the IMRC rod bushings.