Skip the auto shop - Our mechanics make house calls

Q: Intake leak in my engine.

asked by on

My Check Engine light is on with codes P0171 and P0174. I believe the problem is being caused by an intake leak. If it turns out that is not the problem, I have a few other ideas on what can be done to fix it, namely replace the air filter and the front oxygen sensor, and clean the air flow meter.

Codes P0171 and P0174 are lean codes for bank 1 and bank 2 (both sides of the engine). Dozens of problems can cause these codes to set, from a vacuum leak to a clogged fuel injector. While the mass airflow sensor and intake leak could be the problem, you can rule out the air filter. The O2 sensor is also unlikely since you have codes for both banks and it would be unusual for both the upstream O2 sensors to be bad. A trained technician, such as one from YourMechanic, will be able to diagnose and repair your Hyundai.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

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: I started my car this morning and went to put it in drive. As soon as I took my foot off the brake to give gas it shut off completely.

This may be related to a couple of possible things. There is a component called an idle air control valve that monitors the air intake as it is mixed with fuel prior to being injected into the engine at low...

Q: Oil fouls one spark plug - possible cause and recommendations to repair.

Hi there. If oil is causing the spark plug on cylinder number 4 to foul out every 600 to 700 miles, then the valve guide seals to that cylinder are damaged and need replaced. The valve guide seals prevent excessive...

Q: When I press the gas pedal the vehicle misfires

The code P1128 means that the heated oxygen is swapped from the circuitry. Check the wiring on the O2 sensor and check the condition of the O2 sensor. If the sensor is working fine or you have replaced the sensor...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...