Engine Controls - DTC P0171 Set

SOURCE: Honda Service News

TITLE: Got a DTC P0171? Check the Short-Term Fuel Trim

APPLIES TO: 03-04 Accord
01-04 Civic
02-04 CR-V
03-04 Element
02-04 Odyssey
03-04 Pilot

SERVICE TIP:

Got a vehicle in your shop that purrs like a kitten but it sets a DTC P0171 (fuel system too lean)? Check the short-term fuel trim (ST FUEL TRIM B1). If the value reads higher than 1.05, then check the MAP SENSOR value with the engine turned off and the ignition switch turned to ON (II).
- If the MAP SENSOR and BARO SENSOR values match, the MAP sensor is working OK. Do the normal troubleshooting for DTC P0171.
- If the MAP SENSOR and BARO SENSOR values don't match, install a known-good MAP sensor, and retest. If the sensor values now match, clear the DTC, and make sure the ST FUEL TRIM B1 value is normal (it reads about 1.0).