Chart 7
WARNING: This page is about a different car, the 2007 Mercury Mariner and 2007 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.
- - Poor Fuel Economy
NOTE:
Since driving styles can have a significant influence on fuel economy, verify the concern before starting an in-depth diagnosis. Also, the following external factors may contribute to poor fuel economy conditions:
- stop/go driving
- improper tire pressure/size
- vehicle loads (such as trailer towing)
- extended winter warm-up conditions
- high speed driving
- regenerative braking disabled
- high traction battery temperatures
- improper axle ratio
- road/weather conditions
- aftermarket add-ons
- short run operations
- customer expectations
| SYSTEM/COMPONENT |
REFERENCE (Pinpoint Test unless noted) |
- Transaxle Fluid Level
|
- Visual. REFER to AUTOMATIC TRANSAXLE/TRANSMISSION - ELECTRONICALLY CONTROLLED CONTINUOUSLY VARIABLE TRANSMISSION (ECVT)
.
|
- Check the following PIDs:
- LONGFT1 (value between -20 and +20)
- VPWR (value between 10.5 and 17.0 volts, and within 0.5 volt of battery voltage)
|
- LONGFT1 value low (-):
- Continue diagnosis. Concentrate checks in areas that cause the engine to run rich.
- LONGFT1 value high (+):
- Continue diagnosis. Concentrate checks in areas that cause the engine to run lean.
- VPWR not between 10.5 and 17.0 volts:
- REFER to GENERATOR AND REGULATOR
.
- VPWR between 10.5 and 17.0 volts, but not within 0.5 of battery voltage:
- CHECK the B+ supply to the power relay. CHECK the VPWR circuit between the PCM and the power relay. CHECK the PWR GND circuits.
|
- Verify the engine operates at normal temperature.
|
- Visual. REFER to ENGINE COOLING - HYBRID
, to diagnose any cooling system concerns that are present.
|
- Secondary Ignition System
|
- refer to PINPOINT TEST JB
.
|
- Fuel System
|
- refer to PINPOINT TEST HC
.
|
- Exhaust System
|
- refer to PINPOINT TEST HF
.
|
- Automatic Transaxle
|
- REFER to AUTOMATIC TRANSAXLE/TRANSMISSION - ELECTRONICALLY CONTROLLED CONTINUOUSLY VARIABLE TRANSMISSION (ECVT)
.
|
- PCV System
|
- refer to PINPOINT TEST HG
.
|
- Additional Checks:
|
- REFER to the appropriate article.
|
- Additional Testing
|
- refer to PINPOINT TEST Z
.
|