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			After replacing the gasket, I am getting P0171/P0174 codes, but I do not have any vacuum leaks.  What could cause this? 
		
	
		
	
			
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			Join Date: Jul 2012 
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			Low fuel pressure or a bad MAF can also cause lean codes. Do you have an exhaust leak because that can also cause false lean codes  
		
	
		
	
			
			
				
					- Nick  | 
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