P0171 Honda -

Question

1996 Honda accord p0171 should upstream 02 sensor readings be using scan tool

Answer 1

P0171 Fuel system lean

The 02 sensor switch for all 02 this is the standard, .125mv to .825mv and the mid range should pass .450mv.On this particular vehicle you need to check for bais condition, Hold the RPM to 3,000 RPM if the 02 sensor is less than .300mv it bias lean and a replacement is required, If the 02 sensor stay more than .600mv it is bias rich and a replacment is necessary.Any time a 02 sensor on scan tool shows a negative number this is a shorted sensor and a replacement is necessary.