Engine Controls - Basic Diagnostic Procedures: Other

Compression

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 specification if the lowest reading cylinder is within 75 percent of the highest reading cylinder.

WARNING

DO 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.

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

Check battery and charging system condition.
Check all wiring and vacuum connections.
Check air cleaner and ducting.
Check state of tune.
Check fuel delivery system.
Check cooling system.
Check inertia fuel shutoff switch.
Check for hydrostatic lock (liquid in cylinder).
Check fuel tank contents and fuel gauge accuracy.
Check for dirt, water or other contamination in fuel.
Check fuel lines and fittings for leaks.
Check fuel delivery system for proper pressure and volume.
Check for inoperative fuel injectors.
Check for improperly installed electronic equipment such as CB radio, cellular telephone or stereo.

Escort & Tracer

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.

Probe

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 .

Tempo & Topaz

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).
If fuel pressure gauge is not available, disconnect electrical connector to IFS switch. For IFS switch location, see «INERTIA FUEL SHUTOFF (IFS) SWITCH»(ref-22920-S25928048212001121700000) location table under INERTIA FUEL SHUTOFF (IFS) SWITCH. Crank engine for 15 seconds to reduce system pressure.

FUEL PRESSURE

WARNING

ALWAYS 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 199

Release fuel pressure. Install fuel pressure gauge. Connect a jumper wire between fuel pump test terminal at the Data Link Connector (DLC) and ground. (Scheme 199) Turn ignition on, but DO NOT start engine. This activates the fuel pump.
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-123320) article. Turn ignition off and monitor fuel pressure for one minute. Fuel pressure should not drop more than 5 psi (34 kPa).
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.
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 additional fuel system testing information, refer to appropriate SYSTEM/COMPONENT TESTS article as listed below. On EEC-IV and EEC equipped models, see appropriate TESTS W/CODES article as listed below for diagnostic procedure of PCM controlled fuel pump circuits. I - SYSTEM/COMPONENT TESTS - EEC (1.8L) (for Escort & Tracer) I - SYSTEM/COMPONENT TESTS - EEC-IV (1.9L) (for Escort & Tracer) I - SYSTEM/COMPONENT TESTS - EEC-IV (2.0L) (for Probe) I - SYSTEM/COMPONENT TESTS - EEC-IV (2.3L) (for Tempo & Topaz) G - TESTS W/CODES - EEC 1.8L (for Escort & Tracer) G - TESTS W/CODES - EEC-IV (1.9L) (for Escort & Tracer) G - TESTS W/CODES - EEC-IV (2.0L) (for Probe) G - TESTS W/CODES - EEC-IV (2.3L) (for Tempo & Topaz)

Fuel Injector Check

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.
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-22920-S20767346952001121700000) .

Fuel Injector Resistance

Disconnect injector harness connectors. Using digital ohmmeter, measure resistance between injector terminals. If resistance is not 11-19 ohms, replace injector.

Note. For additional testing and information, proceed to FUEL SYSTEM in appropriate SYSTEM/COMPONENT TESTS article below in this section.

I - SYSTEM/COMPONENT TESTS - EEC (1.8L) (for Escort & Tracer)
I - SYSTEM/COMPONENT TESTS - EEC-IV (1.9L) (for Escort & Tracer)
I - SYSTEM/COMPONENT TESTS - EEC-IV (2.0L) (for Probe)
I - SYSTEM/COMPONENT TESTS - EEC-IV (2.3L) (for Tempo & Topaz)

INERTIA FUEL SHUTOFF (IFS) SWITCH

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 below. INERTIA FUEL SHUTOFF (IFS) SWITCH LOCATION Application Location Escort & Tracer Sedan Right Side Of Trunk Wagon Behind Access Door In Right Rear Cargo Area Probe Right Side Of Trunk Tempo & Topaz In Trunk On Left Hinge Support Or Behind Trim Panel
To test inertia switch, turn ignition off. Remove inertia switch. Shake inertia switch to force switch into tripped position (switch open).Measure resistance between appropriate inertia switch terminals. See «WIRING DIAGRAMS»(ref-22920-S26005597442001121700000) . Continuity should be not present between terminals with switch tripped and present when reset.

PRELIMINARY INFORMATION

Note. If an ignition failure occurs, ignition system may operate with limited ability using Failure Mode Effects Management (FMEM). When this occurs, trouble codes should be present, engine may be hard to start and dwell and timing will not change.

IGNITION COIL RESISTANCE

Application	Primary (Ohms)	Secondary (Ohms)
1.8L	0.8-1.6	6000-30,000
1.9L	(1)	(1)
2.0L	0.6-1.1	1150-18,500
2.3L	0.8-1.6	8000-11,500
(1) Resistance value is not provided by manufacturer.

(1)	Resistance value is not provided by manufacturer.

IGNITION COIL RESISTANCE (OHMS @ 68°F (20°C)

Spark Check

Check the EI (high data rate) system (formerly Electronic Distributorless Ignition System - EDIS) for fault codes and repair if necessary. See QUICK TEST in appropriate TESTS W/CODES article as listed below. If no fault codes are present, check ignition system wiring harness connectors for corrosion and tight fit. (Scheme 200) Clean or repair connectors as necessary.
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 strong and consistent at each spark plug (one spark per crankshaft revolution), ignition system is okay. If spark is not present, see IGNITION SYSTEMS in appropriate SYSTEM/COMPONENT TESTS article as listed below. G - TESTS W/CODES - EEC 1.8L (for Escort & Tracer) G - TESTS W/CODES - EEC-IV (1.9L) (for Escort & Tracer) G - TESTS W/CODES - EEC-IV (2.0L) (for Probe) G - TESTS W/CODES - EEC-IV (2.3L) (for Tempo & Topaz) Additional information unavailable for Escort & Tracer 1.8L. I - SYSTEM/COMPONENT TESTS - EEC-IV (1.9L) (for Escort & Tracer 1.9L) I - SYSTEM/COMPONENT TESTS - EEC-IV (2.0L) (for Probe) I - SYSTEM/COMPONENT TESTS - EEC-IV (2.3L) (for Tempo & Topaz)

Scheme 200

Check the DI system (formerly Thick Film Ignition-IV (TFI-IV) system) for fault codes and repair if necessary. proceed to QUICK TEST in appropriate TESTS W/CODES article in this section. Refer to the following menu. If no fault codes are retrieved, check ignition system wiring harness connectors for damage, corrosion and tight fit. (Scheme 201) G - TESTS W/CODES - EEC 1.8L (for Escort & Tracer) G - TESTS W/CODES - EEC-IV (1.9L) (for Escort & Tracer) G - TESTS W/CODES - EEC-IV (2.0L) (for Probe) G - TESTS W/CODES - EEC-IV (2.3L) (for Tempo & Topaz)
If no fault codes are retrieved and vehicle starts, problem is intermittent, go to appropriate TESTS W/O CODES article as listed below. 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. H - TESTS W/O CODES - EEC 1.8L (for Escort & Tracer) H - TESTS W/O CODES - EEC-IV (1.9L) (for Escort & Tracer) H - TESTS W/O CODES - EEC-IV (2.0L) (for Probe) H - TESTS W/O CODES - EEC-IV (2.3L) (for Tempo & Topaz)
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. If spark is not present, refer to the appropriate SYSTEM/COMPONENT TESTS article as listed below for component testing. Also refer to appropriate TESTS W/O CODES - EEC or appropriate TESTS W/O CODES - EEC-IV article as listed above. I - SYSTEM/COMPONENT TESTS - EEC (1.8L) (for Escort & Tracer) I - SYSTEM/COMPONENT TESTS - EEC-IV (1.9L) (for Escort & Tracer) I - SYSTEM/COMPONENT TESTS - EEC-IV (2.0L) (for Probe) I - SYSTEM/COMPONENT TESTS - EEC-IV (2.3L) (for Tempo & Topaz)
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, proceed to appropriate TESTS W/O CODES - EEC and TESTS W/O CODES - EEC-IV articles as listed below. H - TESTS W/O CODES - EEC 1.8L (for Escort & Tracer) H - TESTS W/O CODES - EEC-IV (1.9L) (for Escort & Tracer) H - TESTS W/O CODES - EEC-IV (2.0L) (for Probe) H - TESTS W/O CODES - EEC-IV (2.3L) (for Tempo & Topaz)

Scheme 201

IDLE SPEED & IGNITION TIMING

Ensure idle speed and ignition timing are set to specification. For adjustment procedures, see ADJUSTMENTS - 4-CYL article in this section.

IGNITION TIMING

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

Application	Degrees BTDC @ RPM
1.8L	(1) 9-11
1.9L	(2) (3) 10
2.0L	(2) 9-11
2.3L	(2) 10
(1) With STI terminal grounded. (2) Disconnect single in-line SPOUT connector or remove shorting bar from double wire SPOUT connector.

(1)	With STI terminal grounded.

(2)	Disconnect single in-line SPOUT connector or remove shorting bar from double wire SPOUT connector.

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 - 4-CYL article in this section.

Model	RPM
1.8L	(1) 700-800
1.9L	(2) 730-830
2.0L	(2) 650-750
2.3L	(3)
(1) With STI terminal grounded. (2) Idle speed is not adjustable. (3) Information is not available, refer to underhood label.

(1)	With STI terminal grounded.

(2)	Idle speed is not adjustable.

(3)	Information is not available, refer to underhood label.

IDLE SPEED SPECIFICATIONS

SUMMARY

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