Q: P0171 and P0174 codes

asked by on

My check engine light came on for bank 1 and 2 upstream o2 sensors. I smell raw fuel from engine compartment, and my fuel tank crushed itself causing a hole in the tank. All this occurred after I replacement my fuel cap when the light came on for faulty cap. I've read the vapor canister purge solenoid is the culprit. Is there any truth to that?

For one, these codes are for a lean condition and are not O2 sensor specific codes. It is true that some of the newer Fords have an issue with the purge valve staying on, putting a vacuum on the system that causes the gas tank to collapse. In fact, there is even a technical service bulletin (TSB) regarding this issue, but it does not apply to your vehicle. One thing I would look at first, is the mass air flow (MAF) sensor. There is a TSB 98-23-03 regarding the codes you have setting as a result of a faulty MAF. Of course, Code P0171 and P0174 can be set by anything that causes a lean condition; from a vacuum leak to a faulty fuel pump. To know for certain, I suggest you have a professional, such as one from YourMechanic, diagnose and repair your vehicle firsthand (https://www.yourmechanic.com/services/check-engine-light-is-on-inspection).

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. P0171 and P0174 codes

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Q: Squeaking noise.

Any number of suspension components can squeak when worn. When applying the brakes, weight transfers to the front of the vehicle. This can cause worn components to shift and make noise. ball joints for example. As they age, the grease...

Q: burning smell smoke out of vents, no blowing for air or heat

Hello there, Smoke coming out of the vents is not a common failure point. There are a few possible causes for this though. The most common would be the blower motor resistor, blower motor, heater core failure, wiring fault, or...

Q: Why am I getting rich codes in my 2012 Chevrolet Silverado

Claimed by Robert Tomashek

Related articles

P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...