P0171 and P0174 codes
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Racer
Joined: Sep 2007
Posts: 333
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From: East Coast
P0171 and P0174 codes
Has anybody had these codes thrown after having the battery disconnected or alternator removed for an extended period? I removed my alternator to have a new voltage regulator installed, it was out 2 days, after reinstall, drove for about 1/2 hr., no problems and voltage problem eliminated. Drove the car the next evening and now I have these codes. I checked this morning for any vacuum leaks, short of removing the intake I found none, any help would be greatly appreciated
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Joined: Dec 2002
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From: Lakewood Ranch, FL
Strange as they are Fuel Trim Lean codes for bank 1 and bank 2 respectively. Don't know why your trim would go lean from having the battery disconnected. I'd clear codes and drive it to see if they came back.
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Vacuum hoses for splits, kinks, and proper connections. Refer to Emission Hose Routing Diagram .
Crankcase ventilation valve and/or system for leaks. Refer to Crankcase Ventilation System Description .
Contaminated fuel. Refer to Alcohol/Contaminants-in-Fuel Diagnosis .
PCM and sensor grounds are clean, tight and in the proper locations.
Air induction system after MAF sensor for vacuum leaks.
Engine mechanical failure.
THose are listed if both codes are set (0171 & 0174)
Crankcase ventilation valve and/or system for leaks. Refer to Crankcase Ventilation System Description .
Contaminated fuel. Refer to Alcohol/Contaminants-in-Fuel Diagnosis .
PCM and sensor grounds are clean, tight and in the proper locations.
Air induction system after MAF sensor for vacuum leaks.
Engine mechanical failure.
THose are listed if both codes are set (0171 & 0174)
Moderator emeritus
Joined: Jun 2001
Posts: 18,599
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From: Jacksonville Florida BWO Dayton, Cincinnati, Bloomsbury NJ, Cincinnati
2015 C7 of the Year Finalist
Burning Brakes
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From: Western Kentucky
