Q: Getting code P0131 rough idle, loud, and smell exhaust fumes

asked by on

Similiar issue. While coming out of the store my ML500 started up like a loud truck with rough idle. Plugged it up and got CEL codes P0131 and P0456. I can also smell exhaust fumes, gets louder during exceleration. We changed the O2 sensor to a bosch on "passenger side" code P0456 code went away but still getting P0131, loud/rough idle and exhaust fumes?? Can this be a leak in the exhaust? Cat converter need to be changed? Vacuum Leak? Or fuel filter? This is a major headache! HELP!

My car has 160 miles.
My car has an automatic transmission.

Hello. Codes P0456 and P0131 can come up from a serious exhaust leak. From what you are explaining, it sounds like this is the issue. The exhaust leak will need to be located and repaired before further testing. If there is no exhaust leak, then there may be a leak in the EVAP system from one of the hoses or in the top seal of the fuel tank. If you need to have this looked at, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose the fumes and rough idle.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1,000 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!
  1. Home
  2. Questions
  3. Getting code P0131 rough idle, loud, and smell exhaust fumes

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: Engine coolant temperature on high and no heat inside

Hi there: Overheating problems can be caused by multiple component failures ranging from a heater core that is clogged (as the mechanic suggested), a bad thermostat or coolant leaks and water pump failure. However, one item often overlooked is the...

Q: I installed a boss 302 manifold on my 13 mustang gt 5.0 and the bolt in the middle pasenger side craked but the other bolts are in.

Hi there. The bolt that cracked the manifold will not cause the cylinder 1 to misfire. The misfire is caused by a faulty spark plug, a faulty spark plug wire, a faulty fuel injector, or a burned valve. Check the...

Q: The car has an autocheck report of 90.

Hey there. Failing the emission test is less of a concern than failing a safety inspection. Emission testing failure could be as simple and innocuous as the car having a loose gas cap and setting a DTC. But...

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...
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...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.