Q: DTC: P0171 and DTC:P0174

asked by on November 11, 2017

Hello i have a 2004 f150 4.6 Triton and today when i turnd it on i got DTC: P0171 and DTC:P0174 witch i believe are vacuum leeks is it ok to keep driving it is it hurting aney thing?

My car has 205000 miles.
My car has an automatic transmission.

A number of things may cause code P0171 and P0174 to be triggered. As the codes indicate, this means there is a lean fuel condition which may be caused by a lack of fuel supply or in some cases, a vacuum leak. When a vacuum leak is present, this introduces an excessive amount of air into the fuel/air mixture which results in leaning out the fuel content. Other problems such as a faulty fuel pressure regulator, a faulty fuel pump, a clogged fuel filter, faulty fuel injectors, faulty oxygen sensors, or a faulty mass air flow sensor may also cause this to happen. Continuous driving of the truck in this condition may eventually cause engine damage. I would suggest having a professional from YourMechanic come to your location to diagnose and inspect your vehicle.

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