So I got a P0174 (Bank 2 Lean) code last week. That was the only code, there was no corresponding code for bank 1 being lean as well. So i did a lot of searching and came up with a list of possibilities
- Bad upstream o2 on bank 2 (reading lean)
- Leaky UIM/LIM gasket on the front bank (bank actually is lean)
- Some other crazy way unmetered air could get into only one bank of cylinders
- Intake leak
- Bad IAC or MAF
So after reading some more old threads it seemed that either of the last two would cause codes for both banks being lean, so I put those as the least likely.
I decided to pull a plug from each bank today and have a look, as I figured that would tell me whether or not the bank is actually running lean. I have pulled the middle plug from each bank (cylinders 2 and 5 i suppose) and not only does the front bank plug not look lean, but the plugs from both banks look identical.
these plugs look just a tad lean to me, but my plugs were not that white on the tips.
So, if you have made it this far, here are my ?s.
1)Have I done anythign wrong so far.
2)Is there any way to test whether an O2 sensor is working properly or not without replacing it. I don't have anything I can monitor A/F with as I am driving, but i know that the o2s put out voltages, is there any tests I can do with a multimeter that would give me a hint as to whether or not the sensor is in working order
3)Am I missing any other possible causes that I need to look into.
Thanks,
Cameron
me
