AF=O2 sensor. AF ratio is calculated by how much O2 is left in the exhaust I believe (never really looked up the exact chemistry used). Don't trust the stock "wideband" too much though. It reads poorly below 13:1 and not at all below 11.3:1.
		 
		
		
		
		
		
		
			
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				FWD is the new AWD
			 
		
		
		
		
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