Changes in the design of 4G1 engines since 2001 (Mitsubishi Colt 5)

Technical data of the 4G1 engine after 2001 are given in Table 17.1.

Table 17.1. Technical data of the 4G1 engine after 2001.

Parameters		Nominal value
Resistance of the inlet air temperature sensor, kOhm	20°C	2.3-3.0
	80°C	0.30-0.42
Oxygen sensor output voltage, V		0.6-1.0
Oxygen sensor resistance at 20°C, Ohm	Front	4.5-8.0
	Rear	11-18

Engine Diagnostic Trouble Codes

As soon as one of the following MPI fuel injection system items fails, the engine warning light (Figure 17.1) comes on. If it remains on or comes on when the engine is running, check the fault codes. The engine diagnostic fault codes are listed in Table 17.2. To check the functionality, the warning lights come on for five seconds when the ignition is turned on and then go out.

Table 17.2. Engine diagnostic trouble codes

Fault code	The node being diagnosed
-	Electronic engine control unit
P0105	Vacuum pressure sensor
P0110	Inlet air temperature sensor
P0115	Coolant temperature sensor
P0120	Throttle Position Sensor
P0125	Feedback system
P0130	Front Oxygen Sensor
P0135	Front Oxygen Sensor Heater
P0136	Rear Oxygen Sensor
P0141	Rear Oxygen Sensor Heater
P0170	Engine power supply system
P0201	Nozzle 1
P0202	Nozzle 2
P0203	Nozzle 3
P0204	Nozzle 4
P0300	Ignition failures
P0301	Cylinder 1 misfire
P0302	Cylinder 2 misfire
P0303	Cylinder 3 misfire
P0304	Cylinder 4 misfire
P0325	Knock sensor
P0335	Crankshaft angle sensor
P0340	Camshaft Angle Sensor
P0403	Solenoid valve with exhaust gas recirculation system
P0420	Catalyst
P0421	Catalyst
P0443	Purge air control solenoid valve
P0500	Vehicle speed sensor
P0505	Idle Speed Control System
R1610	Electronic engine immobilizer

Technology for testing units and assemblies

The technology for checking units and assemblies is given in Table 17.3.

Table 17.3. Checking units and assemblies

Checking the Engine Control Unit Connector

The voltage values at the terminals of the engine control unit connector are shown in Table 17.4.

Table 17.4. Voltage values at the terminals of the engine control unit connector

Adjusting the basic idle speed

1. The standard idle speed is adjusted by the manufacturer using the speed adjusting bolt (SAS), so there is no need for such adjustment.

2. If the adjustment is changed intentionally, the idle speed may increase or decrease if the engine is loaded, such as by an air conditioner. In this case, the adjustment should be made as described below.



3. Adjustment is carried out only after the functionality of the spark plugs, injectors, idle drive with booster, compression, etc. has been checked.

4. Connect the MUT-II tester to the diagnostic (16-pin) connector.

5. Start the engine and let it idle.

6. Select item 30 of the tester verification test.

Note: The ISC stepper motor remains in the initial stage so that the basic idle speed can be adjusted.

7. Check the idle speed. Nominal value: 750±50 rpm.

Attention! For a new car (with a mileage of less than 500 km), the engine speed may be 20-100 rpm lower, but adjustment is not necessary in this case. If the engine stalls or the engine speed is too low, although the car's mileage is already more than 500 km, the throttle valve is probably clogged and needs to be cleaned.

8. If the measured value does not correspond to the nominal value, adjust it with the speed adjusting bolt (SAS) (Figure 17.2).



9. Press the reset button of the MUT-II tester and take the ISC stepper motor out of the test mode.

Attention! If you do not do this, the testing mode will continue for 27 minutes.

10. Turn off the ignition.

11. Disconnect the MUT-II tester.

12. Start the engine again and let it idle for 10 minutes. Check the idle speed.

Nozzle

The nozzle is shown in Figure 17.3.