Computer showed PO175- Fuel System Rich, Bank 2. My mechanic suggested that i should get a new o2 sensor. One org. member suggested that it could be fuel pressure regulator.
So my questions are:
1. What is Bank 2 referring to?
2. If it is an o2 sensor, which one(can one tell form the code)?
2. What other possible causes i should be looking at and why?

Thanks.

 

Bank 2 is closest to you when you open the hood....

Running rich can mean a few things. One is that your coils are and not burning the fuel, causing unburned fuel to get into the exhaust stream, therefore fouling the sensors, causing them to read rich thus throwing the code. Being in bank 2, I'd check the front coils.


Some more

Heated oxygen sensor 1 (front)
Injectors
Exhaust gas leaks
Incorrect fuel pressure
Mass air flow sensor

taken from http://www.forums.maxima.org/showthr...75#post3575377

 

If coils are bad wouldn’t they misfire+SES showing a random/single cyl. misfire codes? I had cyl. 3 coil changed for that reason. Is there a visual way to identify bad coils if no codes are present?

I ran fuel injector cleaning fluid like 2 months ago. Just info…




this one? From what i've seen on code chart, Heated O2 Sensor has it's own code and so does MAF, and they weren't showing. http://www.troublecodes.net/infinity/

 

Which coils did they replace?

Running F/I cleaner doesn't matter, it's the electronic properties that we are talking about here which would cause that code.

Yes that one.

 

only coil on cyl #3, which is on the side of firewall(i guess Bank 1..??), was replaced, but that's the only one that was showing at that time.

 

# 3 is in the rear and in the wrong bank relative to this new problem (P0175)

They(1 or more of the front coils) could be on their way out. Or as was suggested by THT in the AM forum, you might have FP issues. I think the more common and likely problem(s) is a front coils is turing ....or the MAF, but you'll know when that dies for good.

 

Yeah, I can't stand the generality of PO175 code! I wish something specific would break so i can replace it and be done with it.

 

hey MAX, you think if I was to replace the o2 sensor just to rule out 1 possibility, would it be a waste since it may get contaminated, like you said?

Thanks.