Q: O2 sensor on exhaust manifold...is it upstream or downstream...09 Nissan Altima

asked by on

Service Engine Soon light is on and I am getting the Catalytic converter replaced. I just need to know which O2 sensor to buy ? Upstream or downstream ?

My car has 21400 miles.
My car has an automatic transmission.

Hey there, thanks for writing in about your 2009 Nissan Altima. The downstream O2 sensor is the sensor used for catalyst efficiency. It is not the one in the manifold but the one after the converter. If you need help with an oxygen sensor replacement, our technicians can come to your location to install the correct the part.

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. O2 sensor on exhaust manifold...is it upstream or downstream...09 Nissan Altima

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: How does the rearview monitor work?

If your car is equipped with a rearview monitor, you have an important tool for increasing safety any time you back up your vehicle. The touchscreen in the center console is connected to a rear-facing camera that turns on whenever...

Q: Can a faulty O2 sensor cause a lean burn?

Hi, thanks for writing in. Yes the O2 sensor can cause the vehicle to run lean. What the O2 sensor does is read the amount of air entering the engine and sends that information to the computer, the computer reads...

Q: My car is bouncing on the back end. I have had struts and shocks replaced, I have purchased new tires, and have had several balan

Hi Bre. Thanks for contacting us tonight. The suspension, wheels, and steering linkage all work together to make sure that your car can drive smoothly and safely. When one of these systems fails, the result can be a car that...

Related articles

How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
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...