Lean / Rich Codes

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NV93Cobra
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Joined: Thu Jul 05, 2012 5:04 pm
Location: Reno, Nevada

Lean / Rich Codes

Post by NV93Cobra »

I'm consistently having the Check Engine Light come on after about 10 minutes of driving the car. When I put the car into to self test mode I get the following codes:

41/91 - Lean during the Continuous Memory Test

and

42/92 - Rich during the Engining Running Test (with the car at operating temperature)

I just don't understand how I'm getting lean codes out of Memory but am getting rich codes during the Run test. I replaced the O2 sensors about a year ago when I initially tried to fix this and this morning I replaced the MAF sensor with what I believe is the correct one (purchased from AutoZone).

Any assistance would be appreciated.
1993 SVT Cobra #4970
1993 Mustang GT (Sold)
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1993cobra
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Re: Lean / Rich Codes

Post by 1993cobra »

vacuum lines, idle air motor, O2 sensors, air filter, timing, catalytic converters fuel pressure regulator, map sensor, ??,
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93Cobra#2771
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Joined: Thu May 11, 2006 2:21 pm
Location: Tennessee

Re: Lean / Rich Codes

Post by 93Cobra#2771 »

Vacuum leak, exhaust leak, mods, etc? And what he said ^--------

Does it say which bank is giving the errors?
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