Interpreting Short Term Fuel Trim: Diagnosis Guide
Short term fuel trim numbers reveal lean and rich combustion conditions. Hosts explain how comparing idle, load, and bank data isolates vacuum leaks and fuel delivery faults.
In this episode
Positive fuel trim indicates lean combustion requiring added fuel
Negative fuel trim indicates rich combustion requiring fuel reduction
Comparing idle trim with twenty-five hundred rpm separates vacuum leaks from fuel starvation
Bank differences isolate bank-specific intake leaks, exhaust leaks, or sensor faults
Links & resources
Read the full article: How To Interpret Short Term Fuel Trim
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The skinny
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