rocky010563

Rest of text is:
O2 Bank 1 Sensor 1
Negative Current, Circuit/Open

From what I researched, this indicates:

• Oxygen sensor is bad
• Bank 1 - right (not sure if this is towards front of car or rear?)
• Sensor 1 - upstream (before cat)

Does the rest of the message mean the heater circuit is bad?

I currently have >60k miles (seems too soon to go bad)? Should I change both upstream O2 sensors (rather pricy)?

rocky010563

The Bosch website states that my Acura take 2 sensors before the catalyst:

• PN 13965 - Oxygen sensor in the front of the engine
• PN 15401 - Oxygen sensor in the rear of the engine

What are the difference between these? Which one corresponds to the "bank 1 sensor 1" message? Should I replace both even though only 64k miles?

rocky010563

Still have heard anything yet. I also have studdering (hesitation) at low acceleration in 3rd gear like many other mention. I am guessing that this can also be the oxygen sensors?

Please can anyone offer their suggestions?
Thanks...

draztic1011

iTrader: (1)

I just got that code myself along with p0174. Did you ever resolve this? Which O2 sensor was it?

cloud0126

These codes were getting thrown by my wife's 2005 Acura MDX. As this thread has explained and as further research shows, these codes refer to Bank 1, Sensor 1. A better description of this is the upstream rear O2 sensor.

The sensor is located on the rear side of the engine towards the firewall...yes, in that tight space in the back of the engine compartment toward the cabin...lovely. It's really tough to get back there, but making the trip to the auto store to get an O2 sensor removal socket is a BIG help. Do yourself a favor and pick up the socket before you start this job, you'll save yourself a ton of time. I picked up a 7/8" O2 removal socket made by OEM at AutoZone for $16; totally worth it.

All I did was remove the top plastic cover from the engine and literally climbed on top of it in order to get to where the sensor is located in the back. There's really no good way to do it; you'll look pretty goofy, but the job is pretty quick, so you won't have to be there for long. If you bought the replacement O2 sensor, you should know what you're looking for. It's facing up, so at least you've got that going for you. Disconnect the cable first before you stick the socket down there to unscrew it. Use a few extender sockets with a breaker bar to get the old one out; it'll be in there pretty good. Put the new one in, connect it up, and you're done!

There's a lot online about "resetting" the computer so that the check engine light goes out, but I just ran the car for about 4 trips, and the light went out on its own. If the light bugs you, I've heard that disconnecting the battery for a few minutes and then re-connecting it will reset the computer. Your preference.