09 C63: CEL P0171 Low Fuel Pressure Bank 1
12-05-2017, 01:10 PM
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2009 C63 P30
09 C63: CEL P0171 Low Fuel Pressure Bank 1
Hey everyone,
So I'm facing an weird problem and unsure how to diagnose this one.
My CEL just went off and its scanned it with a generic obd2 scanner and the code I'm getting is P0171.
From what I know so far, it's a vacuum leak or sensor problem, or hose leaks or could be a huge variety of things.
I need help knowing where to start, how to diagnose this properly myself and is there a proper way to go about finding out.
Once the problem is figured out I have no problem getting the part and replacing and fixing the issue.
I don't really want to bring it to a shop to diagnose it unless I absolutely have no way of finding out the source of the problem.
The trouble is knowing which one is the faulty one.
Any help from pros that had a similar situation or knows how to deal with this is greatly appreciated.
PS: If you need any more info or Pics please feel free to ask.
Thank you again for your time and effort doods
So I'm facing an weird problem and unsure how to diagnose this one.
My CEL just went off and its scanned it with a generic obd2 scanner and the code I'm getting is P0171.
From what I know so far, it's a vacuum leak or sensor problem, or hose leaks or could be a huge variety of things.
I need help knowing where to start, how to diagnose this properly myself and is there a proper way to go about finding out.
Once the problem is figured out I have no problem getting the part and replacing and fixing the issue.
I don't really want to bring it to a shop to diagnose it unless I absolutely have no way of finding out the source of the problem.
The trouble is knowing which one is the faulty one.
Any help from pros that had a similar situation or knows how to deal with this is greatly appreciated.
PS: If you need any more info or Pics please feel free to ask.
Thank you again for your time and effort doods
12-05-2017, 01:48 PM
#2
Member
Since this is getting flagged on only the one bank and not both, start with looking at the parts associated with that bank. I had both 0171 and 0174 (I think this is right) which turned out to be a leak in a hose connection at the back of the intake manifold where the airflow is mixed. What the ECU is telling you is more air than expected is getting into that side of the engine. It detects this based on what the O2 sensors are reading compared to the sensor at the air boxes.
