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PO174 system lean bank 2

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Old Aug 9, 2009 | 05:08 PM
  #1  
78novacaine's Avatar
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From: SE Houston
Default PO174 system lean bank 2

anybody had this code before? car has been running slightly rough but i thought it was due to the bank 1 02 sensor being shot (code scanner confirmed this as well) but as far as i know the o2 sensor being bad puts the car in open loop, which makes it run richer than normal, not lean, so if anyone has any experience with this code please let me know ASAP what it might be. injectors? fuel rail? sensor buggin out for no reason? etc, etc
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Old Aug 9, 2009 | 06:34 PM
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From: East Central Florida
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A O2 sensor having problems staying "lit", can drive
fuel trimming crazy before it finally faults. This is one
possible way to get the "too lean" code, because
there's no difference between lean output and
brain-dead.

If you force it open loop and clear the trims, and
it runs better then mis-trimming is likely. Ditto if
you can see O2s switching or high right after a
good high-load drive, but then get lazy and quit
as you sit and idle.
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