1998 Ford Expedition P0171 code and P0174 pending

[newbcarguy]

I've got this code and trying to diagnose what's the issue. Upon inspection I found this line/hose (image attached) very worn out. Any ideas if this is causing the codes (P0171 and pending P0174)? What part is this?

Thanks for input.

 

[99WhiteC5Coupe]

Those codes indicate the engine is running lean (too much air in the intake stream).

This can be caused by a vacuum leak (bad hoses) and/or a dirty or bad MAF sensor. Do you have any other codes?

The oxygen measurement is taken by the two upstream oxygen sensors. It is possible they are bad or their wiring is damaged. It is unusual for both to go bad at the same time unless some type of contaminant was introduced into the intake system.

It is possible to clean the MAF sensory wires as there are commercial spray products made specifically for the MAF sensor (don’t use throttle body or carburetor cleaner) available at auto parts stores.

 

[Hamfisted]

Very common for that vacuum hose to deteriorate and leak. I've found that the aftermarket Dorman offering doesn't deteriorate like the factory one does. So I would replace it just for insurance. But don't be surprised if there's another leaker hiding in there. When in doubt, always smoke check it.

Dorman 46076 Evap Vacuum Hose on Amazon

Mechanic's Smoke Tester on Amazon





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[newbcarguy]

Very common for that vacuum hose to deteriorate and leak. I've found that the aftermarket Dorman offering doesn't deteriorate like the factory one does. So I would replace it just for insurance. But don't be surprised if there's another leaker hiding in there. When in doubt, always smoke check it.

Dorman 46076 Evap Vacuum Hose on Amazon

Mechanic's Smoke Tester on Amazon





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Thanks for your input. I got the same part now and I will see if that fixes my issue. Wil update ASAP.

 

[newbcarguy]

Those codes indicate the engine is running lean (too much air in the intake stream).

This can be caused by a vacuum leak (bad hoses) and/or a dirty or bad MAF sensor. Do you have any other codes?

The oxygen measurement is taken by the two upstream oxygen sensors. It is possible they are bad or their wiring is damaged. It is unusual for both to go bad at the same time unless some type of contaminant was introduced into the intake system.

It is possible to clean the MAF sensory wires as there are commercial spray products made specifically for the MAF sensor (don’t use throttle body or carburetor cleaner) available at auto parts stores.

Thank you for your input. No other error codes. I'm in the process of replacing that fuel evap line. I am afraid there is a bigger issue such as bad sensors or a bigger leak. I will update after replacing the hose.

 

[CplKev72]

I fixed a vac leak, and cleaned the maf sensor with CRC Mass Air Flow Sensor Cleaner spray. It ran better but was still surging, and missing a little. Replaced the maf sensor with a new one, and that fixed it. Runs like a top.
Also if your canister is bad you will know when fueling up it will keep stopping (clicking the pump handle off) like it is full.