U0401 Engine Code Repair

Meaning of U0401 engine trouble code is a kind of network trouble code and when your car's 'U0401 Check Engine' light comes on, it's usually accompanied by a sinking feeling in the pit of your stomach. The light could mean a costly problem, like a bad catalytic converter, or it could be something minor, like a loose gas cap. But in many cases, it means at minimum that you'll be visiting the car dealer to locate the malfunction and get the light turned off.

U0401 Fault Symptoms :

U0401 Possible Solution:

Excessive air inflow can be caused by a vacuum leak, a dirty sensor or, an exhaust gas recirculation valve not closing properly. If the problem is not enough fuel, the culprit may be dirty injectors or fuel filters, a weak fuel pump or a leaky fuel pressure regulator. The lean fuel mix error may be accompanied by rough idling, engine misfires, hesitation during acceleration and overall poor engine performance.

U0401 Code Meaning :

The oxygen (02) sensors on your car measure the oxygen in the exhaust to determine how rich or lean the ratio of fuel and air are in the cylinders. Optimizing this mixture means better fuel economy and fewer exhaust emissions.

Parts or components should not be replaced with reference to only a U0401 DTC. The vehicle service manual should be consulted for more information on possible causes of the fault, along with required testing.