Poor Fuel Economy
WARNING: This page is about a different variant/trim than selected.
- Heavy loads being carried or towed
- Acceleration rate too much or too often
- Inspect the brake system for brake drag.
- Inspect for incorrect operation of the speedometer.
- Verify that the engine coolant temperature (ECT) has not shifted in value. Refer to Temperature Versus Resistance .
- Inspect the mass air flow (MAF) sensor for obstruction, contamination, and damage. Refer to Throttle Body Assembly Replacement .
- Inspect for foreign material accumulation in the throttle bore, and for carbon deposits on the throttle plate and shaft. Also inspect for throttle body tampering.
- Start and run the vehicle until fully warm. Observe the CMP variation parameter while accelerating up to 1,500 RPM and back to idle several times. The CMP variation should indicate a value for 1-2 seconds, then return to 0 degree. If the camshaft actuator responds erratic, inconsistent, or not at all, refer to Camshaft Position Actuator Magnet Cleaning and Inspection and Camshaft Position Actuator Cleaning and Inspection .
IMPORTANT:
A vehicle with a camshaft actuator either stuck at full camshaft retard, in the Park position, or uncontrolled and wandering, may experience poor fuel economy.