Engine Controls - Basic Testing: Other Eagle Summit I

Compression

Check engine mechanical condition with a compression gauge, vacuum gauge, or an engine analyzer. See engine analyzer manual for specific instructions.

COMPRESSION SPECIFICATIONS

Exhaust System Backpressure

Exhaust system can be checked with a vacuum or 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 1 3/4-2 psi, exhaust system or catalytic converter is plugged.

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

FUEL SYSTEM

Relieving Fuel Pressure

1. Remove rear seat cushion to disconnect fuel pump harness connector. Start engine. Let engine run until it stops. Turn ignition off. Disconnect negative battery terminal. Connect fuel pump harness connector. Reinstall rear seat (if necessary.) WARNING: Before disconnecting high pressure fuel hose at fuel delivery pipe, cover fuel hose connection with a rag. Some residual fuel pressure may still be in system.

Scheme 15

1. Disconnect high pressure fuel hose at fuel delivery pipe. Remove throttle body bracket (if necessary). Connect fuel pressure gauge with adapter between fuel delivery pipe and high pressure hose. (Scheme 15)
2. Connect negative battery terminal. Connect battery voltage to fuel pump test terminal. See «FUEL PUMP TEST TERMINAL LOCATION»(ref-18863-S01443262142001010800000) table. Ensure no fuel leaks are present. Disconnect battery voltage to fuel pump test terminal.
3. Start engine and let idle. Measure fuel pressure with vacuum hose connected to fuel pressure regulator. Record fuel pressure reading. Disconnect and plug vacuum hose from fuel pressure regulator. Record fuel pressure reading. See «FUEL PUMP PERFORMANCE»(ref-18863-S20834039592001010800000) table.
4. Check for fuel pressure in fuel return hose by gently pinching hose while increasing engine speed. If fuel volume is low, fuel pressure in return hose will not be felt. Increase engine speed to 2500-3000 RPM, 2-3 times. Return engine to idle. Fuel pressure should not drop when engine is returned to idle.
5. Turn ignition off. On all models except Precis, ensure fuel pressure reading does not decrease within 2 minutes. On Precis, fuel pressure reading should not decrease within 5 minutes. On all models, if a decrease is noted, monitor speed of decrease.
6. If fuel pressure is lower than specification, fuel pressure drops at idle after increasing engine speed to 2500-3000 RPM, or no fuel pressure in fuel return hose can be felt, check for clogged fuel filter, or faulty fuel pressure regulator or fuel pump.
7. If fuel pressure is higher than specification, check for a faulty fuel pressure regulator or plugged fuel return line. If fuel pressure does not change when vacuum hose to regulator is connected or disconnected, check for a leaking or clogged vacuum hose to fuel pressure regulator or faulty fuel pressure regulator.
8. If fuel pressure decreases suddenly after engine is stopped, check valve within fuel pump is not seated. Replace fuel pump. If fuel pressure drops slowly, fuel injector is leaking or fuel pressure regulator valve seat is leaking. Check for faulty fuel injector or fuel pressure regulator. Repair as necessary.
9. When fuel pressure test is complete, repeat fuel pressure release procedure before disconnecting fuel pressure gauge. Install new "O" ring at end of high pressure hose. Check for fuel leaks. FUEL PUMP TEST TERMINAL LOCATION Application Wire Color Location 1.5L BLK/WHT Center Of Firewall 1.6L BLK/BLU Center Of Firewall FUEL PUMP PERFORMANCE Application (1) At Idle psi (kg/cm 2 ) (2) At Idle psi (kg/cm 2 ) All Models 38 (2.6) 47-50 (3.3-3.5) (1) With vacuum at pressure regulator. (2) Without vacuum at pressure regulator.

MPI Control Relay

Multipurpose relay switches power to vehicle sensors and actuators including airflow sensor, crank angle sensor, idle speed control, injectors and fuel pump. When ignition switch is turned to ON position, ECU energizes coils controlling injectors, airflow sensor and idle speed control. When ignition switch is turned to START position, ECU energizes coils (through inhibitor switch on A/T models) to supply power to fuel pump. Relay failure will cause a no-start condition. For testing procedure, see SYSTEM/COMPONENT TESTS article.

SPARK

Check for spark at coil wire (if applicable) and at each spark plug wire using a high output spark tester. Check spark plug wire resistance on suspect wires. For wire resistance specification, see SPECIFICATIONS article.

CRANK ANGLE SENSOR

For crank angle sensor testing procedure, see SYSTEM/COMPONENT TESTS article.

Scheme 16

Scheme 17

1. Using a Digital Volt-Ohmmeter (DVOM), measure primary coil resistance between ignition coil connector terminals No. 2 and 3 (coils for cylinders No. 1 and 4) and terminals No. 1 and 3 (coils for cylinders No. 2 and 3). (Scheme 16)
2. Disconnect ignition coil connector. Measure secondary coil resistance between coil towers for cylinders No. 1 and 4 and between coil towers for cylinders No. 2 and 3. (Scheme 17) Primary and secondary coil resistance should be within specification. See «IGNITION COIL RESISTANCE (1.6L)»(ref-18863-S16275738592001010800000) table. IGNITION COIL RESISTANCE (1.6L) Ohms @ 68°F (20°C) Application Primary Secondary Mirage.77-.95 10,300-13,900

Scheme 18

Scheme 19

1. To test power transistor coil for No. 1 and 4 cylinders, disconnect power transistor connector. Using a 1.5-volt dry cell battery, connect negative end of 1.5-volt battery to terminal No. 3 of power transistor and positive end of 1.5-volt battery to power transistor terminal No. 7 as shown in STEP 1. (Scheme 18)
2. Using an analog ohmmeter, check for continuity between terminals No. 3 and 8 of power transistor. Continuity should exist. With positive end of 1.5-volt battery disconnected, no continuity should exist. Replace power transistor if it does not test as specified.
3. To test power transistor coil for No. 2 and 4 cylinders, connect negative end of 1.5-volt dry cell battery to terminal No. 3 of power transistor and positive end of 1.5-volt battery to power transistor terminal No. 2 as shown in STEP 2. (Scheme 19)
4. Using an analog ohmmeter, check for continuity between terminals No. 1 and 3 of power transistor. Continuity should exist. With positive end of 1.5-volt battery disconnected, no continuity should exist. Replace power transistor if it does not test as specified.

Ignition Coil Resistance

Using a DVOM, measure primary coil resistance between positive and negative terminals of coil. (Scheme 20) Measure secondary coil resistance between coil positive terminal and ignition coil tower. Primary and secondary coil resistance should be within specification. See IGNITION COIL RESISTANCE (1.5L) table.

IGNITION COIL RESISTANCE (1.5L) - Ohms @ 68°F (20°C)

Scheme 20

Scheme 21

1. Disconnect power transistor connectors. Using a 1.5-volt dry cell battery, connect negative end of 1.5-volt battery to terminal No. 7 of power transistor and positive end of 1.5-volt battery to power transistor terminal No. 8. (Scheme 21)
2. Using an analog ohmmeter, check for continuity between terminals No. 2 and 7 of power transistor. Continuity should exist. With positive end of 1.5-volt battery disconnected, no continuity should exist. Replace power transistor if it does not test as specified.

Scheme 22

1. Disconnect power transistor connector. Using a 1.5-volt dry cell battery, connect negative end of 1.5-volt battery to terminal No. 5 of power transistor and positive end of 1.5-volt battery to power transistor terminal No. 6. (Scheme 22)
2. Using an analog ohmmeter, check for continuity between terminals No. 5 and 12 of power transistor. Continuity should exist. With positive end of 1.5-volt battery disconnected, no continuity should exist. Replace power transistor if it does not test as specified.

IDLE SPEED & IGNITION TIMING

Ensure idle speed and ignition timing are set to specification. See IGNITION TIMING SPECIFICATIONS table. For adjustment procedures, see ADJUSTMENTS article.

IGNITION TIMING SPECIFICATIONS (Degrees BTDC @ RPM)

SUMMARY

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