Routine No. 13 - Poor Fuel Economy
While fuel consumption is drastically increased for short-run operation, stop and go driving, trailer towing, extended winter warm up periods, etc., as opposed to "trip" mileage, an attempt should be made to determine these factors when confronted with "poor mileage" conditions. However, since the operator is not always at fault, the following is offered.
ROUTINE NO. 13 - POOR FUEL ECONOMY
| System | Component | Reference |
|---|---|---|
| Throttle Body | Electrical & Vacuum Connections, Throttle Plates & Linkage | Visual & Fuel System Components |
| Induction | Air Duct & Hoses, (Poor Connection or Restricted), Filter Element, Vane AFM | Visual & Fuel System Components |
| Ignition | Scope Engine For: Spark Plugs, Coil, Secondary Wires, Distributor Cap and Rotor | Ignition System Mechanical Components |
| EEC | Quick Test | QUICK TEST Procedures |
| Fuel Delivery | Lines (Leaking), Return Line (Blocked), Pump, Injectors | Fuel System Mechanical Components |
| Cooling | Thermostat | Cooling System Components |
| Ignition Timing | Base plus Advance and Retard Functions | Ignition Mechanical Components |
| Factors External To The Engine | Tire Pressure & Type, Clutch Operation, Automatic Transaxle, Shift Pattern and Fluid Level, Brake Drag, Exhaust System, Vehicle Load, Road & Weather Conditions | Mechanical Components |