Note: Perform this check after checking the idle speed.
1. Before starting the inspection and adjustment procedures, prepare the vehicle (see section "Checking the idle speed").
2. Check that the basic ignition timing is within the nominal value (see section "Checking and adjusting the ignition timing").
3. If during the test the tester was not connected, then turn off the ignition and then connect the tester to the diagnostic socket.
4. Start the engine and let it run at 2000-3000 rpm for 2 minutes.
5. Install the gas analyzer probe (CO and CH) into the exhaust pipe.
6. Measure the concentrations of CO and CH at idle, which must correspond to the nominal values.
Rated values (no more):
GDI engines:
- CO concentration - 0.1%
- CH concentration - 100 min-1
Engine 4G15-MPI:
- CO concentration - 0.1%
- CH concentration - 100 min-1
Engine 4G93-MPI:
- CO concentration - 0.5%
- CH concentration - 100 min-1
Note: For a GDI engine, measurements should be taken within 4 minutes of running the engine at idle speed.
7. If the concentrations deviate from the nominal values, it is necessary to perform troubleshooting and check the fuel injection system. In most cases, it is sufficient to perform checks according to the following points:
- A) Checking trouble codes (output signal of the diagnostic system);
- b) (Except 4G93-MPI engine) Checking the feedback control system:
Note: In case of normal operation of the feedback control system, the output of the oxygen sensor changes from 0 to 0.4 V and from 0.6 to 1.0 V at idle.
- V) Fuel pressure check;
- G) Checking injectors;
- d) Checking ignition coils;
- e) (MPI motors) Checking high voltage spark plug wires, w) Checking spark plugs;
- e) Checking the components of the exhaust gas recirculation system.
- and) Checking the fuel vapor recovery system;
- h) Compression check.
Note: The three-way catalytic converter must be replaced if the CO and CH concentrations are above the rated values and all of the above checks are normal.
8. Turn off the ignition and disconnect the tester.