Troubleshooting System too Lean Codes
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AudiWorld Member
Joined: Feb 2004
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Troubleshooting System too Lean Codes
I've been having a System too Lean error code on both banks and was wondering if you anyone ever figured out how to trouble shoot it. (I searched the archives)
I get three codes 17546 & 17544 System too lean banks 2 & 1. They don;t give me a CEL, but they cause a third one 17688 Air Control Valve Flow too low, that does.
Any idea how to try and trouble shoot this ?
I get three codes 17546 & 17544 System too lean banks 2 & 1. They don;t give me a CEL, but they cause a third one 17688 Air Control Valve Flow too low, that does.
Any idea how to try and trouble shoot this ?
Thread Starter
AudiWorld Member
Joined: Feb 2004
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I do now...
I never used the cd version, but I have it for this car. I'll try tracing it down with that as well. I just know that this issue was brought up last december or so, but I couldn;t find the final resolution in the archives.
Junior Member
Joined: Jan 2005
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Put the codes in the search field on Bentley
That should get you to the right page and then you can run some measuring blocks to track down the problems.
Here are some possibilities I got for the first two codes:
Perform road test (fuel in engine oil)
- Check fuel pressure regulator and residual pressure Page 24-33
- Check Mass Air Flow (MAF) sensor -G70- Page 24-125
- Check HO2S Page 24-53
- Check fuel tank level Page 24-160
- Check Evaporative Emissions (EVAP) canister purge regulator valve Page 24-104
And what I got for the last one.
- Check air control valve for fuel injectors -N212- Page 24-109
Here are some possibilities I got for the first two codes:
Perform road test (fuel in engine oil)
- Check fuel pressure regulator and residual pressure Page 24-33
- Check Mass Air Flow (MAF) sensor -G70- Page 24-125
- Check HO2S Page 24-53
- Check fuel tank level Page 24-160
- Check Evaporative Emissions (EVAP) canister purge regulator valve Page 24-104
And what I got for the last one.
- Check air control valve for fuel injectors -N212- Page 24-109
New Member
Joined: Dec 2002
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Sounds like legit fault. Would discount oxygen sensors for
now, as the third code about the idle circuit seems to verify the others. Would be vigilant for vacuum leaks, with a suspect eye on the maf sensor as a possible source of faulty input data.
Member
Joined: May 2004
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Re: check for vacuum leaks
Mine threw off the same code and I nearly went crazy looking for it. After 3 tries, I found the problem- a vacuum hose was broken near the base of one of the fuel injectors. A little Hylomar and about 50 miles and the light went off.
Phil C
Phil C
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