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Engine Controls - Tests W/o Codes - Gasoline: Other Ford Aerostar I

INTERMITTENT SIMULATION

To reproduce the conditions that create an intermittent fault so it may be identified during testing, some of the following methods may be used

  1. Applying light vibration to components.
  2. Heating a component.
  3. Wiggling or bending a wiring harness.
  4. Applying humidity to a component.
  5. Removing or applying a vacuum supply source.

Monitor circuit/component voltage or resistance while attempting to simulate intermittent. If vehicle is running, monitor for self-diagnostic codes. See TESTS W/CODES article. Use the results of these tests to identify a faulty component or an area that should be closely checked for the problem.

Note. For additional information on connecting test equipment and operating Continuous Monitor Mode test procedures, see TESTS W/CODES article.

ROUTINE 200 - NO CRANK & NO START

SYSTEM & Component(s)GO TO
STARTING: Battery, Starter Relay, Starter, Neutral Drive Switch/ Clutch Switch/Brake Interlock Switch, Ignition Switch, Transmission Linkage AdjustmentCharge or replace battery, check charging and starting systems
EEC: Neutral Drive Switch/ Clutch SwitchSee TESTS W/CODES article
BASIC ENGINE: Flywheel, Engine SeizedCheck engine mechanical condition
FUEL DELIVERY: InjectorsSee SYSTEM/COMPONENT TESTS article

ROUTINE 200 - NO CRANK & NO START

ROUTINE 201 - CRANKS NORMALLY BUT WON'T START

Note. Extended cranking due to a "NO START" condition, can load exhaust system with raw fuel. This can ruin the catalytic converter after engine is started. After a "NO START" condition has been repaired, disconnect the thermactor air supply, run the engine until surplus fuel is used up and reconnect the thermactor air supply.

SYSTEM & Component(s)GO TO
EEC: Quick TestSee TESTS W/CODES
IGNITION (ALL TYPES): Electrical Connections, Secondary Ignition Wires, Spark Plugs Fouled, Ignition SwitchSee SYSTEM/COMP TESTS
IGNITION (DSII & TFI IV): Ignition Coil or Module, Rotor Alignment, Distributor Cap, Adapter, Rotor & StatorSee SYSTEM/COMP TESTS
IGNITION (DIS/EDIS): Single or Dual Hall Crank Sensors, Hall Camshaft Sensor Ignition Module & Coil pack(s)See SYSTEM/COMP TESTS
FUEL DELIVERY: Filter, Pump, Contamination in Fuel Lines, Tank (Fuel Supply), Dual Tank Selector Switch, Sender Filter, PFI & TBI Pressure regulator, Injectors & Inertia SwitchSee SYSTEM/COMP TESTS
FUEL CHARGING ASSY: Electrical Connections, Throttle LinkagesSee SYSTEM/COMP TESTS
BASIC ENGINE: Camshaft Timing, CompressionCheck engine mechanical condition
EGR: ValveSee SYSTEM/COMP TESTS
EXHAUST: Catalyst ExhaustVisually inspect for blockage

ROUTINE 201 - CRANKS NORMALLY BUT WON'T START

ROUTINE 202 - CRANKS NORMALLY BUT WON'T RUN (STALLS)

SYSTEM & Component(s)GO TO
FUEL CHARGING ASSY: Curb or Fast Idle Speed, Electrical & Vacuum ConnectionsSee SYSTEM/COMP TESTS
EEC: Quick TestSee TESTS W/CODES
FUEL DELIVERY: Filter, Pump, Contamination in Fuel Lines, Tank (Fuel Supply), Dual Tank Selector Switch, Sender Filter, Fuel Pressure Regulator, Injectors & Inertia SwitchSee SYSTEM/COMP TESTS
IGNITION (DSII & TFI IV): Ignition Coil or Module, Rotor Alignment, Dist. Cap, Adapter, Rotor & StatorSee SYSTEM/COMP TESTS
IGNITION (DIS/EDIS): Single or Dual Hall Crank Sensors, Hall Camshaft Sensor Ignition Module & Coil pack(s)See SYSTEM/COMP TESTS
EXHAUST: Component (Restricted)Inspect exhaust system
EGR: ValveSee SYSTEM/COMP TESTS
BASIC ENGINE: Camshaft & Valve TrainCheck engine mechanical condition

ROUTINE 202 - CRANKS NORMALLY BUT WON'T RUN (STALLS)

ROUTINE 203 - CRANKS NORMALLY BUT SLOW TO START

Note. It is a good practice to confirm that the correct starting procedure was being used by the customer proceeding with diagnosis.

SYSTEM & Component(s)GO TO
IGNITION (DSII & TFI IV): Distributor Cap, Adapter & RotorSee SYSTEM/COMP TESTS
IGNITION (DIS/EDIS): Single or Dual Hall Crank Sensors, Hall Camshaft Sensor Ignition Module & Coil Pack(s)See SYSTEM/COMP TESTS
EEC: Quick TestSee TESTS W/CODES
FUEL DELIVERY: Filter, Pump, Contamination in Fuel lines, Tank (Fuel Supply), Dual Tank Selector Switch, Sender Filter, Fuel Pressure Regulator, InjectorsSee SYSTEM/COMP TESTS
FUEL CHARGING ASSY: Curb or Fast Idle speed, Electrical & Vacuum ConnectionsSee ADJUSTMENTS
EXHAUST: Component (Restricted)Check exhaust system
INDUCTION & VACUUM DISTRIBUTION: Vacuum leaks, Air Cleaner Element RestrictedPerform a visual inspection
COOLING: Electric Fan (Hot Start Only)Check cooling system
EGR: ValveSee SYSTEM/COMP TESTS
PCV: ValveSee SYSTEM/COMP TESTS
EVAP: ComponentsSee SYSTEM/COMP TESTS

ROUTINE 203 - CRANKS NORMALLY BUT SLOW TO START

ROUTINE 204 - ROUGH IDLE

SYSTEM & Component(s)GO TO
COOLING: Fan or Electric Fan (Loose or Cracked)Perform a visual inspection
IGNITION: Scope Engine for: Spark Plug, Coil, Secondary Wires, Distributors Cap, Adapter, Rotor & Ignition TimingSee SYSTEM/COMP TESTS
EEC: Quick TestSee TESTS W/CODES
FUEL CHARGING ASSY: Curb or Fast Idle Speed, Electrical & Vacuum ConnectionsSee SYSTEM/COMP TESTS & ADJUSTMENTS
FUEL DELIVERY: Fuel Pressure Regulator, Injectors, Fuel RailSee SYSTEM/COMP TESTS
VACUUM DISTRIBUTION: Vacuum LeaksPerform a visual & audible inspection
EGR: Valve, Vacuum RegulatorSee SYSTEM/COMP TESTS
COOLING: ThermostatCheck cooling system
BASIC ENGINE: Compression, Valve Train, Camshaft, Intake Manifold GasketsCheck engine mechanical condition
PCV: ValveSee SYSTEM/COMP TESTS
EVAP: ComponentsSee SYSTEM/COMP TESTS
EXHAUST: Pipes, Muffler, Catalyst Resonator, Heat Control ValveCheck exhaust system

ROUTINE 204 - ROUGH IDLE

ROUTINE 205 - MISSES UNDER LOAD

SYSTEM & Component(s)GO TO
IGNITION: Scope Engine for: Spark Plug, Coil, Secondary Wires, Distributors Cap, Adapter, Rotor & Ignition TimingSee SYSTEM/COMP TESTS
EEC: Quick TestSee TESTS W/CODES
FUEL DELIVERY: Filter, Pump, Lines, Fuel Pressure Regulator Sender Filter, InjectorsSee SYSTEM/COMP TESTS
FUEL CHARGING ASSY: Electrical andVacuum ConnectionsSee I SYSTEM/COMP TESTS and ADJUSTMENTS
EGR: ValveSee SYSTEM/COMP TESTS

ROUTINE 205 - MISSES UNDER LOAD

ROUTINE 206 - LOW IDLE (STALLS ON DECEL OR QUICK STOP)

SYSTEM & Component(s)GO TO
FUEL CHARGING ASSY: Curb or Fast Idle speed, Electrical & Vacuum Connections, Throttle DevicesSee SYSTEM/COMP TESTS
EEC: Quick TestSee TESTS W/CODES
EGR: ValveSee SYSTEM/COMP TESTS
BASE TRANSMISSION (E40D ONLY): Transmission Oil Level, Converter Clutch Control SolenoidCheck transmission

ROUTINE 206 - LOW IDLE (STALLS ON DECEL OR QUICK STOP)

ROUTINE 207 - HESITATES OR STALLS ON ACCELERATION

SYSTEM & Component(s)GO TO
EEC: Quick TestSee TESTS W/CODES
IGNITION: Scope Engine for: Spark Plug, Coil, Secondary Wires, Distributor Cap, Adapter, Rotor & Ignition TimingSee SYSTEM/COMP TESTS
FUEL CHARGING ASSY: Curb or Fast Idle speed, Electrical & Vacuum ConnectionsSee ADJUSTMENTS and SYSTEM/COMP TESTS
FUEL DELIVERY: Filter, Pump, Contamination in Fuel lines, Switch, Sender Filter, Fuel Pressure Regulator, InjectorsSee ADJUSTMENTS and SYSTEM/COMP TESTS
VACUUM DISTRIBUTION: Vacuum LeaksPerform a visual & audible inspection
INDUCTION: Air Cleaner Duct, Stove Pipe & Valve Inter-Cooler Tube (Air Leaks)See SYSTEM/COMP TESTS
EGR: ValveSee SYSTEM/COMP TESTS
PCV: ValveSee SYSTEM/COMP TESTS
EXHAUST (RESTRICTION): With Back Pressure EGR SystemSee SYSTEM/COMP TESTS
BASE TRANSMISSION (E40D & A4LD): Converter Clutch, Control, Solenoid OverrideSee TESTS W/CODES

ROUTINE 207 - HESITATES OR STALLS ON ACCELERATION

ROUTINE 208 - BACKFIRE (INTAKE OR EXHAUST)

SYSTEM & Component(s)GO TO
IGNITION: Scope Engine for: Spark Plug, Coil, Secondary Wires, Distributor Cap, Rotor Ignition Timing, crossed WiresSee BASIC TESTING
VACUUM DISTRIBUTION: Vacuum hoses, or Connections Leak(s)Perform a visual & audible inspection
EEC: Quick TestSee TESTS W/CODES
THERMACTOR: Thermactor System ComponentsSee SYSTEM/COMP TESTS
PULSE Air: Pulse Air System ComponentsSee SYSTEM/COMP TESTS
BASIC ENGINE: Compression, Valve Train, Camshaft, Intake Manifold GasketsCheck engine mechanical condition
EXHAUST: Components (Restricted)Check exhaust system
Fuel DELIVERY: Filter, Pump, Contamination in Fuel lines, Sender Filter, Fuel Pressure Regulator, InjectorsSee ADJUSTMENTS and SYSTEM/COMP TESTS

ROUTINE 208 - BACKFIRE (INTAKE OR EXHAUST)

ROUTINE 209 - LACK OF POWER

SYSTEM & Component(s)GO TO
IGNITION: TimingSee G - ADJUSTMENTS
EEC: Quick TestSee TESTS W/CODES
FUEL DELIVERY: Filter, Pump, Lines, Sender Filter, Fuel Pressure, Regulator InjectorsSee SYSTEM/COMP TESTS
FUEL CHARGING ASSY: Curb or Fast Idle Speed, Electrical & Vacuum ConnectionsSee BASIC TESTING and SYSTEM/COMP TESTS
IGNITION: Scope Engine for: Spark Plug, Coil, Secondary Wires, Distributor Cap, Rotor & Ignition Timing, Crossed WiresSee BASIC TESTING
EXHAUST: Components (Restricted)Check exhaust system
COOLING: ThermostatCheck cooling system
VACUUM DISTRIBUTION: Vacuum Leak(s)Perform a visual & audible inspection
INDUCTION: Air Cleaner Duct, Valve & ElementSee SYSTEM/COMP TESTS
EGR: ValveSee SYSTEM/COMP TESTS
BASIC ENGINE: Compression Check, Camshaft, ValveSee BASIC TESTING
DRIVE TRAIN: Clutch, Automatic Transmission, BrakesCheck transmission & drive train components

ROUTINE 209 - LACK OF POWER

ROUTINE 210 - SURGES AT STEADY SPEED

SYSTEM & Component(s)GO TO
EEC: Quick TestSee TESTS W/CODES
FUEL DELIVERY: Filter, Pump, Lines, Sender Filter, Fuel Pressure RegulatorSee SYSTEM/COMP TESTS
FUEL CHARGING ASSY: Curb or Fast Idle Speeds Electrical & Vacuum ConnectionsSee ADJUSTMENTS
IGNITION: Scope Engine for: Spark Plug, Coil, Secondary Wires, Distributor Cap, Rotor Ignition Timing, Crossed WiresSee BASIC TESTING
VACUUM DISTRIBUTION: Vacuum Leak(s)Perform a visual & audible inspection
EGR: ValveSee SYSTEM/COMP TESTS
INDUCTION: Air Cleaner Duct & Valve & ElementSee SYSTEM/COMP TESTS
EVAP: ComponentsSee SYSTEM/COMP TESTS
BASIC ENGINE: Valve Train & Camshaft Intake Manifold GasketsSee BASIC TESTING
THERMACTOR: Thermactor System ComponentsSee SYSTEM/COMP TESTS

ROUTINE 210 - SURGES AT STEADY SPEED

ROUTINE 211 - HIGH IDLE, ENGINE "DIESELS"

Note. If engine Idles smoothly after key is turned off, trouble is likely to be in the Ignition Switch, Ignition harness, starter solenoid "IGN" tap, or EEC relay

SYSTEM & Component(s)GO TO
FUEL CHARGING ASSY: Curb or Fast Idle Speed, Electrical & Vacuum Connections, Throttle Positioner, Throttle Plate & LinkageSee BASIC TESTING and SYSTEM/COMP TESTS
VACUUM DISTRIBUTION: Vacuum Leak(s)Perform a visual & audible inspection
EEC: Quick TestSee TESTS W/CODES
INDUCTION: Vacuum LeaksPerform a visual & audible inspection
COOLING: OverheatingCheck cooling System

ROUTINE 211 - HIGH IDLE, ENGINE "DIESELS"

ROUTINE 213 - POOR FUEL ECONOMY

Note. Since Fuel consumption is drastically increased for city driving, 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 appended.

SYSTEM & Component(s)GO TO
FUEL CHARGING ASSY: Electrical & Vacuum ConnectionsSee ADJUSTMENTS
FUEL DELIVERY: Fuel Return Line Blocked, Fuel Pressure RegulatorSee BASIC TESTING
INDUCTION: Air Cleaner Duct & Valve, Air Cleaner Element (Restricted)Perform a visual inspection
IGNITION: Scope Engine for: Spark Plug, Coil, Secondary Wires, Distributor Cap, Rotor & Adapter Ignition Timing, Crossed WiresSee BASIC TESTING
EEC: Quick TestSee TESTS W/CODES
COOLING: ThermostatCheck cooling System
FACTORS EXTERNAL TO THE ENGINE: Tire Pressure & Type, Clutch Operation, Converter Clutch Override, Automatic Transmission Shift Pattern & Fluid Level, Brake Drag, Exhaust System, Speedometer/Odometer Gear & Axle Ratio, Vehicle Load, Road & Weather Conditions, Aftermarket Add-OnsPerform a manual and visual inspection
BASE Transmission (E40D ONLY): Converter Clutch Control SolenoidSee TESTS W/CODES

ROUTINE 213 - POOR FUEL ECONOMY

ROUTINE 214 - HIGH OIL CONSUMPTION

Note. If the condition can not be verified, clean engine, if necessary, change oil and Filter (at customer expense), seal and have customer drive 500 miles (804.5 Km) or enough Distance to consume two quarts before returning for re- examination.

SYSTEM & Component(s)GO TO
EXTERNAL LEAKS: Rocker Cover Gasket, Crankshaft Seals, Engine AssemblyPerform a visual inspection
PROPER DIPSTICK: Overfilling (sometimes accomplished by the "short stick" gas station procedure)Perform a manual and visual inspection
INDUCTION: Air Cleaner Element (Sealing)Perform a visual inspection
PCV: ValveSee SYSTEM/COMP TESTS
INTERNAL LEAKS (BLUE SMOKE FROM TAILPIPE): Valve Guides & Stem Seals, Intake Manifold & Gasket, Cylinder Head Drain Passages, Piston RingsCheck engine mechanical condition

ROUTINE 214 - HIGH OIL CONSUMPTION

ROUTINE 215 - SPARK KNOCK (PINGS)

SYSTEM & Component(s)GO TO
IGNITION: TimingSee ADJUSTMENTS
EEC: Quick TestSee TESTS W/CODES
VACUUM DISTRIBUTION: Vacuum Leaks PVSPerform a visual & audible inspection, See SYSTEM/COMP TESTS
COOLING: OverheatingCheck cooling System
BASIC ENGINE: Oil Level, Compression Check, Intake Manifold GasketSee BASIC TESTING
FUEL DELIVERY: InjectorsSee SYSTEM/COMP TESTS
PCV: ValveSee SYSTEM/COMP TESTS
EGR: Verify Correct Application, Then DiagnoseSee SYSTEM/COMP TESTS
INDUCTION: Air Cleaner Duct & Valve AssemblySee SYSTEM/COMP TESTS
THERMACTOR: Thermactor System ComponentsSee SYSTEM/COMP TESTS
BASE Transmission (E40D NON-DIESEL ONLY): Transmission ControlsSee TESTS W/CODES

ROUTINE 215 - SPARK KNOCK (PINGS)

Note. If the above fails to correct the condition, it is recommended that the owner change his source of Fuel and use higher octane Fuel.

ROUTINE 216 - ENGINE VIBRATES AT NORMAL OR HIGH SPEED

SYSTEM & Component(s)GO TO
ENGINE ACCESSORIES: Fan, Belt Driven Components, Engine Mounts & Engine Vibration DamperPerform a manual and visual inspection
OTHERWISE: Non-Engine Components: Drive Line, Tires, Wheel BalancePerform a manual and visual inspection

ROUTINE 216 - ENGINE VIBRATES AT NORMAL OR HIGH SPEED

ROUTINE 217 - ENGINE RUNS COLD

SYSTEM & Component(s)GO TO
GAUGE System: Gauge, SenderSee appropriate article in the ACCESSORIES & EQUIPMENT section
COOLING: ThermostatCheck cooling System

ROUTINE 217 - ENGINE RUNS COLD

ROUTINE 218 - ENGINE RUNS HOT

SYSTEM & Component(s)GO TO
COOLING: Thermostat, Coolant Level, Radiator or A/C Condenser, Pressure Cap & Overflow System, External Leaks, Belts & Belt Tension, Fan & Fan Clutch, Electric Fan (if so equipped)See BASIC TESTING
GAUGE System: Gauge, SenderSee appropriate article in the ACCESSORIES & EQUIPMENT section
EEC: Quick TestSee TESTS W/CODES
IGNITION: TimingSee ADJUSTMENTS
BASIC ENGINE: Oil Level, Internal Leak(s), Core Sand in Head/Block, Water PumpCheck engine mechanical condition
BRAKE: Brakes (Dragging)Check brake system

ROUTINE 218 - ENGINE RUNS HOT

ROUTINE 219 - EXHAUST SMOKE

Note. White smoke is normal during warm-up.

SYSTEM & Component(s)GO TO
BLACK SMOKE (RICH MIXTURE): Air Cleaner Element (Restricted), Fuel Pressure Regulator Injectors, EEC ComponentsPerform a visual inspection, See SYSTEM/COMP TESTS , see TESTS W/CODES
BLUE SMOKE (BURNING OIL): PCV Valve, Valve Guides/Stems/Seals, Oil Drain Passages in Head Rings (not seated, seized, gummed up, worn), Cylinder Bores (scuffed)See BASIC TESTING , see engine mechanical condition
WHITE SMOKE (COOLANT IN COMBUSTION): Thermactor Vacuum Delay Valve (restricted), EGR Cooler, Intake Manifold (cracked/porous), Cylinder Head/Gasket (Leaks), Block (cracked/porous)See I - SYSTEM/COMP TEST

ROUTINE 219 - EXHAUST SMOKE

ROUTINE 220 - GAS SMELL

SYSTEM & Component(s)GO TO
FUEL DELIVERY: Injectors (Leaking), Fuel Filter, Fuel Pump, Fuel Line, Fuel Pump to Tank, Fuel Tank, Fuel Tank filler neck/Cap (Leaks), Fuel Return Line (Blocked), Fuel Pressure RegulatorSee SYSTEM/COMP TESTS
EVAP: Carbon Canister, Solenoid, Hoses (Leaks)See SYSTEM/COMP TESTS

ROUTINE 220 - GAS SMELL

ROUTINE 221 - "CHECK ENGINE" OR "SERVICE ENGINE SOON" LIGHT ALWAYS OR NEVER ON "CHECK ENGINE"/"CHECK DCL" MESSAGE ON

SYSTEM & Component(s)GO TO
EEC: Quick TestSee TESTS W/CODES

ROUTINE 221 - "CHECK ENGINE" OR "SERVICE ENGINE SOON" LIGHT ALWAYS OR NEVER ON "CHECK ENGINE"/"CHECK DCL" MESSAGE ON

ROUTINE 223 - IMPROPER SHIFT

SYSTEM & Component(s)GO TO
BASE, TRANSMISSION (E4OD, A4LD, AXOD ONLY): Converter Clutch, Control Solenoid, Electronic Pressure Control Solenoid, Shift Solenoid #1 & #2, 4WD low SwitchSee TESTS W/CODES
EEC (E4OD, A4LD ONLY): Quick TestSee TESTS W/CODES

ROUTINE 223 - IMPROPER SHIFT

ROUTINE 224 - SHIFT INDICATOR LIGHT (SIL) & AUDIBLE CHIMES "ON"

Note. Verify that the customer has read the owners manual on the new 3.8L SC overheat protection feature.

The 3.8L SC is equipped with a Shift indicator light and audible chime that warns the customer when the engine oil or coolant overheats while the vehicle is operated at high Speeds (above 100 MPH) for extended periods of time. The Shift indicator light and chime will also warn the customer when the engine has reached too high an RPM for that gear.

The EEC-IV processor will reduce vehicle Speed by limiting Fuel to the engine when one of these overheat conditions has been reached. The customer may then notice a loss of power and/or a slight vibration. The Shift indicator light will illuminate and the audible chime will produce a steady tone, alerting the customer to upshift at this time. Full power will be restored and the Shift indicator light and chimes will turn off when the vehicle returns to normal operating temperatures.

SYSTEM & Component(s)GO TO
EEC: Shift Indicator Light Bulb "SIL" Dimmer Relay Top Gear SwitchSee TESTS W/CODES
3.8L SC ONLY: Audible Chime SystemSee appropriate article in the ACCESSORIES & EQUIPMENT section

ROUTINE 224 - SIL & AUDIBLE CHIMES "ON"