Error Codes 41 and 91 KOEO Test - Ford Mustang Forums : Mustang Forum
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post #1 of 1 Old 03-31-2004, 06:40 PM Thread Starter
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Question Error Codes 41 and 91 KOEO Test

I have noticed my engine light comming on for a while now.

I believe these are the codes I recieved. I tested with key on engine off and after getting the 11 code it proceeded to give me the 41 and 91 code which not a valid KOEO code but it is a valid Key on engine on code which means a lean condition in bank 1 and 2.

I have a brand new gt40 motor, new O2 sensors, new 24 injectors, new SC Trim, new everything and timing is at 10.

Does any one know what I need to do to make sure I can get rid of these codes?

please help


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