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Emissions Workshop- Fuel Trim Bank 1 Running Too Lean Error

1.4K views 3 replies 2 participants last post by  swett  
#1 ·
#4 ·
Here's the link. First block is idle, second it part throttle. Both should be fairly small, less than 5 typically. If you have a CEL, one is probably larger than 10. First usually indicates a leak in one of the vacuum lines, second is more likely a boost leak. But it could be a bad O2 sensor or a bunch of other problems. Best to check the bentley for the full list of what you should check.

http://www.ross-tech.com/vag-com/m_blocks/030-049.html

-Ian