Contents Wiring diagrams Section: Testing & Diagnostics All sections

Engine Controls - Basic Testing - 4-CYL: Other Ford Escort V facelift

Testing & Diagnostics 6 illustrations ~1730 words

Compression

WARNINGDO NOT use ignition switch during compression tests on fuel injected vehicles. Use a remote starter to crank engine. Fuel injectors on many models are triggered by ignition switch during cranking mode, which can create a fire hazard or contaminate the engine's oiling system.

Check engine mechanical condition with a compression gauge, vacuum gauge, or an engine analyzer. See engine analyzer manual for specific instructions. Compression pressures are considered within specifications if the lowest reading cylinder is within 75 percent of the highest reading cylinder.

Exhaust System Backpressure

The exhaust system can be checked with a vacuum or pressure gauge. If using a pressure gauge, remove O2 sensor or air injection check valve (if equipped). Connect a 0-5 psi pressure gauge and run engine at 2500 RPM. If exhaust system backpressure is greater than 2 psi, exhaust system or catalytic converter is plugged.

If using a vacuum gauge, connect vacuum gauge hose to intake manifold vacuum port. Start engine. Observe vacuum gauge. Open throttle part way and hold steady. If vacuum gauge reading slowly drops after stabilizing, check exhaust system for restriction.

PRELIMINARY CHECKS

Check that the following systems and components are in good condition and operating properly before diagnosing problems in fuel injection system

  1. Check battery condition.
  2. Check all wiring and vacuum connections.
  3. Check air cleaner and ducting.
  4. Check state of tune.
  5. Check fuel delivery system.
  6. Check cooling system.
  7. Check inertia fuel shutoff switch.
  8. Check for hydrostatic lock (liquid in cylinder).
  9. Check fuel tank contents and fuel gauge accuracy.
  10. Check for dirt, water or other contamination in fuel.
  11. Check fuel lines and fittings for leaks.
  12. Check fuel delivery system for proper pressure and volume.
  13. Check for inoperative fuel injectors.
  14. Check for improperly installed electronic equipment such as CB radio, cellular telephone or stereo.

1.8L & 1.9L

Depress retaining clips and remove rear seat cushion. Disconnect fuel pump connections. Start engine and operate until it stalls. Turn ignition off. Reconnect fuel pump. Install rear seat cushion.

2.0L A/T

Remove fuel pump relay or move reset switch on Inertia Fuel Shutoff (IFS) Switch. Fuel pump relay is located in engine compartment main fuse panel. The IFS switch is located on right side of trunk. Start engine and operate until it stalls. Turn ignition off. Reconnect fuel pump relay or reset IFS switch. See INERTIA FUEL SHUTOFF (IFS) SWITCH .

All Others

  1. Remove fuel cap to release fuel tank pressure. Remove relief valve cap. Relief valve is located on fuel supply manifold. Using Fuel Pressure Gauge (T80L-9974-B), release fuel pressure from relief valve (Schrader valve).
  2. If fuel pressure gauge is not available, disconnect electrical connector to IFS switch. For IFS switch location, see «INERTIA FUEL SHUTOFF (IFS) SWITCH»(ref-22785-S14511834762001010300000) location table under INERTIA FUEL SHUTOFF (IFS) SWITCH. Crank engine for 15 seconds to reduce system pressure.

FUEL PRESSURE

WARNINGALWAYS relieve fuel pressure before disconnecting any fuel injection-related component. DO NOT allow fuel to contact engine or electrical components. See FUEL PRESSURE RELEASE .

Note. For fuel pressure specifications, see FUEL PRESSURE SPECIFICATIONS article.

Scheme 1

Scheme 1
  1. Release fuel pressure. Install fuel pressure gauge. On all models except 1.8L and 2.0L A/T, connect a jumper wire between ground and fuel pump test terminal at the Data Link Connector (DLC). (Scheme 1) On 1.8L and 2.0L A/T, connect a jumper wire between ground terminal (Black wire) and fuel pump terminal (Light Green wire) at the Data Link Connector (DLC). On all models, turn ignition on, but DO NOT start engine. This activates the fuel pump. CAUTION: Do not activate fuel pump for long periods, or engine may hydrostatically (liquid) lock.
  2. Measure and record Key On, Engine Off (KOEO) fuel pressure. Start engine. Measure and record Key On, Engine Running (KOER) fuel pressure. For fuel pressure specifications, see «FUEL PRESSURE SPECIFICATIONS»(ref-123319) article. Turn ignition off and monitor fuel pressure for one minute. Fuel pressure should not drop more than 5 psi (kg/cm 2 ).
  3. If fuel pressure is within specification, test is complete. If fuel pressure is not within specification, check fuel filter and lines for restriction(s). Repair or replace as necessary. If fuel pressure is still not within specification, install fuel pressure gauge (if removed). CAUTION: Inspect fuel system for leaks or damage before testing fuel pump.
  4. Start engine and observe fuel pressure gauge. Gently squeeze fuel return hose. If fuel pressure increases while squeezing fuel return hose, replace fuel pressure regulator. If fuel pressure does not change while squeezing fuel return hose, check for plugged fuel inlet strainer or defective fuel pump. Repair as necessary.

Note. For fuel circuit test information, on all models except 1.8L and 2.0L A/T, see TESTS W/CODES - EEC-IV article in the ENGINE PERFORMANCE Section. For 1.8L and 2.0L A/T, see FUEL SYSTEM in SYSTEM/COMPONENT TESTS - ECC article in the ENGINE PERFORMANCE Section.

Fuel Injector Check

  1. Connect tachometer to engine. Run engine at idle. Disconnect and reconnect injectors individually. When disconnected, each injector should cause a momentary drop in engine speed of at least 100 RPM. Engine RPM drop should only be momentary as Powertrain Control Unit (PCM) will attempt to re-establish correct idle RPM.
  2. Replace any injectors that do not cause sufficient drop in engine speed. When test is complete, check idle speed. Refer to emission control specifications on decal in engine compartment. See «IDLE SPEED & IGNITION TIMING»(ref-22785-S42029922382001010300000) .

Fuel Injector

On sequential PFI engines, disconnect injector harness connectors. Using digital ohmmeter, check connector terminal resistance of each injector. If resistance is not 11-18 ohms, replace injector. On non-sequential PFI engines, disconnect injector bank harness connector. Check resistance of injector bank. See INJECTOR BANK RESISTANCE table. Repair wiring or any injector not within specification.

EngineOhms
2.3L6.0-8.5
(1) Resistance values are for non-sequential PFI engines only.
(1)Resistance values are for non-sequential PFI engines only.

INJECTOR BANK RESISTANCE (1)

Note. For additional testing and information, see FUEL SYSTEM in appropriate SYSTEM/COMPONENT TESTS article in the ENGINE PERFORMANCE Section.

INERTIA FUEL SHUTOFF (IFS) SWITCH

  1. If IFS switch is tripped, engine cannot be restarted until switch is manually reset. To reset IFS switch, depress switch button. For IFS switch location, see INERTIA FUEL SHUTOFF (IFS) SWITCH LOCATION table. CAUTION: DO NOT reset inertia switch until fuel system has been inspected for leaks. INERTIA FUEL SHUTOFF (IFS) SWITCH LOCATION Application Location Escort & Tracer Sedan Right Side Of Trunk Wagon Behind Access Door In Right Rear Cargo Area Mustang Lower Left Center Of Trunk Probe Right Side Of Trunk All Others In Trunk On Left Hinge Support Or Behind Trim Panel
  2. To test inertia switch, turn ignition off. Remove inertia switch. Shake inertia switch to force switch into tripped position (switch open).Measure resistance between inertia switch terminal. See «INERTIA SWITCH RESISTANCE»(ref-22785-S17338597092001010300000) table. Replace switch if resistance is incorrect, or if switch cannot be tripped.
Switch PositionOhms
Open (1)10,000+
Closed (2)0-5
(1) Indicates switch is in the tripped position. (2) Indicates switch is in the set position.
(1)Indicates switch is in the tripped position.
(2)Indicates switch is in the set position.

INERTIA SWITCH RESISTANCE

IGNITION COIL RESISTANCE

ApplicationPrimarySecondary
Distributor Ignition (DI)
1.8L0.08-1.66,000-30,000
2.0L A/T0.58-1.1011,500-18,500
All Others0.8-1.68,000-11,500
Electronic Ignition (EI)
High Data Rate(1)(1) **
Low Data Rate(1)(1) **
(1) Resistance values are not available. For testing procedure, see IGNITION SYSTEMS in SYSTEM/COMPONENT TESTS - ECC-IV article in ENGINE PERFORMANCE Section.
(1)Resistance values are not available. For testing procedure, see IGNITION SYSTEMS in SYSTEM/COMPONENT TESTS - ECC-IV article in ENGINE PERFORMANCE Section.

IGNITION COIL RESISTANCE

Spark Output Check

  1. Check the EI (low data rate) system (formally Distributorless Ignition System - DIS) for fault codes and repair if necessary. See QUICK TEST in TESTS W/CODES - EEC-IV article in the ENGINE PERFORMANCE Section. If no fault codes are retrieved, check ignition system wiring harness connectors for corrosion and tight fit. (Scheme 2) Clean or repair connectors as necessary.
  2. If wiring and connectors are okay, use Neon Bulb Spark Tester (D89P-6666-A) to check for spark at each spark plug wire while cranking engine. If spark is consistent and equal at each spark plug (one spark per crankshaft revolution), ignition system is okay. If spark is not present, go to IGNITION SYSTEMS in SYSTEM/COMPONENT TESTS - ECC-IV article in the ENGINE PERFORMANCE Section.

Scheme 2

Scheme 2
  1. Check the EI (high data rate) system (formally Electronic Distributorless Ignition System - EDIS) for fault codes and repair if necessary. See QUICK TEST in TESTS W/CODES - EEC-IV article in the ENGINE PERFORMANCE Section. If no fault codes are retrieved, check ignition system wiring harness connectors for corrosion and tight fit. (Scheme 3) Clean or repair connectors as necessary.
  2. If wiring and connectors are okay, use Neon Bulb Spark Tester (D89P-6666-A) to check for spark at each spark plug wire while cranking engine. If spark is consistent and equal at each spark plug (one spark per crankshaft revolution), ignition system is okay. If spark is not present, go to IGNITION SYSTEMS in SYSTEM/COMPONENT TESTS - ECC-IV article in the ENGINE PERFORMANCE Section.

Scheme 3

Scheme 3
  1. Check the DI system (formally Thick Film Ignition-IV (TFI-IV) system) for fault codes and repair if necessary. See QUICK TEST in appropriate TESTS W/CODES - EEC-IV article in the ENGINE PERFORMANCE Section. If no fault codes are retrieved, check ignition system wiring harness connectors for damage, corrosion and tight fit. (Scheme 5)or (Scheme 6).
  2. If no fault codes are retrieved and vehicle will start, go to appropriate TESTS W/O CODES article in the ENGINE PERFORMANCE Section. If no fault codes are retrieved and vehicle is a no-start, connect a high-output spark tester between ignition coil wire and engine ground. Check for spark at coil wire while cranking engine. A consistent Blue spark should be present.
  3. If spark is present, go to step 4). If no spark is present, remove distributor cap and crank engine to ensure distributor rotates. If okay, check resistance of coil secondary wire. Resistance should be less than 7000 ohms per foot. Service coil wire if necessary and retest. On all models except 1.8L and 2.0L A/T, if spark is not present, go to IGNITION SYSTEMS in SYSTEM/COMPONENT TESTS - ECC-IV article in the ENGINE PERFORMANCE Section. On 1.8L and 2.0L A/T, if spark is not present, go to TESTS W/O CODES article in the ENGINE PERFORMANCE Section.
  4. On all models, if a consistent Blue spark is present at coil wire during cranking, inspect distributor cap and rotor for cracks or carbon tracking. Service as necessary and test spark output at spark plugs. If spark is present at spark plugs and engine will not start, go to appropriate TESTS W/O CODES article in the ENGINE PERFORMANCE Section.

Scheme 4

Scheme 4

Scheme 5

Scheme 5

Scheme 6

Scheme 6

IDLE SPEED & IGNITION TIMING

Ensure idle speed and ignition timing are set to specification. For adjustment procedures, see ADJUSTMENTS article in the ENGINE PERFORMANCE Section.

IGNITION TIMING

Note. Ignition timing is not adjustable on models with Electronic Ignition (low or high data rate).

ApplicationDegrees BTDC @ RPM
4-Cylinder
1.8L(1) 10 @ 750
1.9L(1) 10 @ 815
2.0L11-13 @ 650-750
2.3L
A/T(2) 10 @ 625
M/T(2) 10 @ 675
(1) With STI terminal grounded. (2) With SPOUT in-line connector disconnected.
(1)With STI terminal grounded.
(2)With SPOUT in-line connector disconnected.

BASE IGNITION TIMING

IDLE SPEED

Engine idle RPM is fixed and cannot be changed by standard adjustments. A scan tool must be used because control strategy and idle speed is controlled by Powertrain Control Unit (PCM). See IDLE SPEED in ADJUSTMENTS article in the ENGINE PERFORMANCE Section.

ModelRPM
4-Cylinder
1.8L700-800
1.9L730-830
2.0L700-800
2.3L
A/T500-800
M/T450-750

IDLE SPEED SPECIFICATIONS

SUMMARY

If no faults were found while performing BASIC DIAGNOSTIC PROCEDURES, proceed to appropriate TESTS W/CODES article in the ENGINE PERFORMANCE Section. If no hard codes are found in self-diagnostics, proceed to appropriate TESTS W/O CODES article in the ENGINE PERFORMANCE Section for diagnosis by symptom (i.e., ROUGH IDLE, NO START, etc.) or intermittent diagnostic procedures.