Models with petrol engines
Note 1. Below are the norms for the content of harmful impurities in the exhaust gases of cars with gasoline engines, in force in Russia at the time of writing this Guide. The norms are regulated by GOST R 52033-2003, introduced on 01/01/2004 to replace the previously valid GOST 17.2.2.03-87.
Note 2. GOST uses the following terminology:
- Two-componentexhaust gas aftertreatment system - a system that reduces the content of exhaust gases, mainly carbon monoxide and hydrocarbons, without feedback on the composition of the working mixture.
- Three-componentexhaust gas aftertreatment system - feedback system (according to the excess air coefficient AJ, providing a reduction in the content of carbon monoxide, hydrocarbons and nitrogen oxides in the exhaust gases. □ Carbon monoxide content (SO) and hydrocarbons (NS) in the exhaust gases of cars is determined when the engine is idling for two crankshaft speeds set by the manufacturer for this model: minimum (nmin) and increased (nnos).
□ If there is no such data, then the check is carried out under the following conditions:
- Value nmin should not exceed 1100 min-1
- Value nnos set within:
2500 - 3500 min-1 for cars. not equipped with an exhaust gas aftertreatment system; 2000 - 3500 min-1 for vehicles equipped with an exhaust gas aftertreatment system.
□ To perform this work, you will need an exhaust gas analyzer with a relative error of no more than 6%:
- for models not equipped with neutralization systems or equipped with two-component (oxidative) neutralization systems.
- – a two-channel gas analyzer designed to measure the content of carbon monoxide (SO) and hydrocarbons (CH);
- for models equipped with three-way neutralization systems;
- four-channel gas analyzers designed to measure the content of CO, CH, carbon dioxide (COa) and oxygen (O2).
Four-channel gas analyzers can also be used to perform measurements on vehicles not equipped with neutralization systems or equipped with two-component neutralization systems.
If you do not have such a device and there is no way to borrow it for a while, then almost any auto repair shop will do this job for you for a moderate fee.
□ Before starting measurements, by visual inspection, check the availability of systems and devices on the vehicle that ensure the reduction of harmful emissions. If the actual equipment of the car does not correspond to the one installed by the manufacturer, it makes no sense to perform measurements - you will not pass the technical inspection.
□ Before measurement, the car engine must be warmed up to a temperature not lower than the operating temperature of the engine oil or coolant specified in the vehicle's operating instructions, but not lower than 60°C.
□ After warming up the engine, prepare the vehicle for measurements in the following order:
- install gear lever (or mode selector for vehicles with automatic transmission) to neutral position:
- apply the parking brake and turn off the engine;
- connect tachometer and oil temperature gauges (if it is included in the set of measuring equipment);
- insert the sampling probe of the gas analyzer into the exhaust pipe of the car to a depth of at least 300 mm from the cut (with an oblique cut of the exhaust pipe, the depth is measured from the short edge of the cut).
□ On models not equipped with an aftertreatment system, measure in the following order:
- before taking measurements, check and set zero readings of the gas analyzer on the CO and HC measurement scales;
- start the engine by depressing the throttle pedal, increase the engine speed nnos and work in this mode for at least 15 seconds;
- release the accelerator pedal, set the minimum engine speed nmin and not earlier than after 30 seconds, measure the content of carbon monoxide CO and hydrocarbons HC;
- set a higher engine speed nmin and not earlier than after 30 seconds, measure the content of CO and HC.
□ On vehicles equipped with an aftertreatment system, measure in the following order:
- before taking measurements, check and set zero readings of the gas analyzer on the CO, HC and CO measurement scales2;
- start the engine by depressing the throttle pedal, increase the engine speed to nmin, maintain this mode for 2... 3 minutes (at ambient temperature below 0°C — 4...5 min) and after stabilization of the readings, measure the content of CO, HC, and also fix the value of the coefficient of excess air λ;
- set the minimum motor shaft speed nmin and not earlier than 30 seconds later, measure the content of carbon monoxide and hydrocarbons. Start measuring at nmin should be no later than 30 seconds after checking in mode nmin.
□ On vehicles equipped with a three-component exhaust gas aftertreatment system and a built-in diagnostic system, before measuring the CO and HC content, check the performance of the engine and the neutralization system according to the readings of the diagnostic indicator located on the dashboard:
- when the ignition is turned on, before starting the engine, the diagnostic indicator should turn on for a short period of time; in the absence of a corresponding signal of the diagnostic indicator after the ignition is turned on, the further verification procedure is stopped;
- after starting the engine, the diagnostic indicator should turn off; if the diagnostic indicator remains on while the engine is running, the further verification procedure is stopped.
The content of CO and HC in the exhaust gases
The content of CO and HC must be within the data set by the vehicle manufacturer, but not more than:
Car equipment | Pdv | CO% | NS,million-1 |
Vehicles produced before 01.10.86 | nmin | 4.5 | - |
Vehicles not equipped with the system | nmin | 3.5 | 1200 |
exhaust gas neutralization | nnos | 2.0 | 600 |
Vehicles equipped with a two-component | nmin | 1.0 | 400 |
exhaust gas aftertreatment system | nnos | 2.0 | 200 |
Vehicles with a three-way system | nmin | 0.5 | 100 |
exhaust gas aftertreatment and equipped | |||
on-board diagnostic system | nnos | 0.3 | 100 |
The value of the coefficient of excess air λ in idle mode at nnos for vehicles equipped with a three-way neutralization system, it must be within the data set by the manufacturer. In the absence of such data, λ should be between 0.97 and 1.03.
Models with diesel engines
□ The only test diesel engines undergo (according to GOST 21393-75), is to measure the density of smoke in the exhaust gases. The tests are carried out in the free acceleration mode and in the maximum speed mode.
Note. The good condition of the camshaft drive belt is extremely important for a successful test.
The following are the maximum allowable smoke levels for exhaust gases from diesel engines:
- Measurement mode - Smoke%, no more
- When accelerating the rotation of the crankshaft:
- naturally aspirated - 40
- supercharged - 50
- At the maximum shaft speed - 15
□ Elevated exhaust smoke may be caused by a dirty air filter. In other cases, to establish the cause, you will need to consult a professional.
Requirements for the technical condition of the car and engine
Exhaust system | Completeness (the absence of any elements of the exhaust system is not allowed). tightness (exhaust gas leakage due to loose connections, rust, mechanical damage, etc. is not allowed). |
Neutralization system and other equipment to reduce harmful emissions | Completeness (the absence of any elements of the neutralization system, fuel vapor recovery system, exhaust gas recirculation, etc. is not allowed). |
Crankcase ventilation system | Completeness of the system. The tightness of the elements. |
Built-in engine diagnostic system | Diagnostic Indicator Functioning Corresponding to Proper Engine Operation (indicator when the engine is running is off). |