2. Turn off the ignition and connect the MUT-III device to the diagnostic connector.
3. Check that the base ignition timing angle matches the nominal value.
Nominal value: approximately 10° BTDC
4. Start the engine and let it run at 2500 rpm for 2 minutes.
5. Install a gas analyzer to check CO and CH.
6. Measure the concentrations of CO and CH in idle mode, which should correspond to the nominal values.
Nominal value:
- CO concentration - 0.5% or less;
- CH concentration is 100 ppm or less.
7. If the concentration deviates from the nominal values, the following must be checked:
- Checking the output signal of the diagnostic system;
- Feedback control system (in case of normal operation of the feedback control system, the output signal of the oxygen sensor varies from 0 to 400 mV and from 600 to 1000 mV at idle);
- Fuel pressure;
- Nozzles;
- Ignition coil, spark plug wires and spark plugs;
- No leaks in the exhaust gas recirculation (EGR) system and EGR valve;
- Fuel vapor recovery system;
- Compression.
Note: If the CO and HC concentration exceeds the nominal values (even if the test results for all the above-mentioned items [elements] are normal), the three-way catalytic converter must be replaced.