The engine start procedure is a basic skill of any driver, but in extreme conditions or in case of malfunctions, it can turn into a difficult task. Many motorists perceive the ignition key rotation as a routine action, without thinking about the complex chemical and physical processes occurring at this moment under the hood. Understanding the principles of the starter, ignition and fuel supply system allows you not only to feel confident at the wheel, but also to respond quickly to unforeseen situations, such as a frosty morning or a discharged battery.
Modern engine control systems have made life much easier for vehicle owners, making the start process almost automatic. However, electronic control (ECU) require certain conditions for proper operation, the neglect of which can lead to unsuccessful launch attempts. In this article, we will analyze the algorithms of actions for different types of power units, consider the features of cold start and analyze common mistakes that drivers make.
Do not forget that the correct launch technique directly affects the power unit resource. Sharp movements, prolonged scrolling by the starter or ignoring the signals of the dashboard can cause premature wear of expensive nodes. Competent approach to operation combustion engine (ICE) in the first seconds of its operation is the key to a long and trouble-free service of your car.
Preparation of the vehicle for the first launch
Before you turn the key in the ignition lock or press the Start button, you need to perform a number of preparatory actions that are often ignored by beginners. The initial diagnosis of the condition of the car takes only a minute, but can prevent many problems. First of all, you should visually assess the technical condition of the machine to eliminate obvious obstacles to a safe start.
Check whether the car is worth the cost of parking brake (handle) Starting the engine in the transmission without squeezed clutch or without the handheld on can lead to a sharp jerk of the car and an accident. For automatic transmissions, it is critical to make sure the selector is in position. Park or NeutralMany modern ECUs block the launch in other modes.
⚠️ Warning: If you smell a strong smell of gasoline or diesel in the cabin or under the hood, it is strictly forbidden to try to start the engine. This may indicate a leak of fuel, which creates a high risk of fire at the first spark.
It is also worth paying attention to the indicators on the dashboard. After the ignition (first click of the key) should light the lamps check the engine, oil pressure and battery charge. If the oil pressure lamp does not light up at all, this may indicate a fault in the circuit or the sensor itself, which requires attention before further operation. Ignoring signals self-diagnostics This can cause the engine to start with critical faults.
Before the first start after a long idle, it is recommended to press the brake pedal several times (for cars with a vacuum amplifier) to make sure that it is working, although the engine itself will not start it.
Algorithm of starting a gasoline engine with an injector
Most modern cars are equipped with a distributed fuel injection system known as an injector. The process of starting such motors is as automated as possible and requires minimal driver intervention. The electronic control unit independently calculates the required amount of fuel and the angle of ignition advance, based on the readings of many sensors.
For a successful start, you need to squeeze the clutch pedal (on the mechanics) or the brake (on the machine) and turn the ignition key. At this moment fuel-pump creates the necessary pressure in the ramp, and the nozzles supply the fuel-air mixture to the cylinders. If the engine is serviceable, it should start within 2-3 seconds of scrolling the starter.
- 🔑 Insert the key into the lock and turn it into the power position (wait 2-3 seconds for pressure pumping).
- 🦶 Press the clutch pedal to the end (for manual transmission) or brake (for automatic transmission).
- 🔄 Turn the key to the “Starter” position and hold it until launch, but no longer than 10 seconds.
- 🛑 Immediately after launch release the key, it will return to the "Ignition" position.
It is important not to "overtake" the starter. If the engine is not catching on the first attempt, pause for 30-60 seconds. This time is necessary to ensure that battery He regained his charge and the starter cooled. Long continuous operation of the starter can lead to its overheating and failure, as well as to a deep discharge of the battery.
☑️ Check before starting the injector
Features of starting carburetor engines
Owners of classic car models, such as VAZ-2101-2107, and some foreign cars of the last century, face the need to manually adjust the mixture to run. The carburetor has no electronics, so the preparation of the engine for start-up depends on the ambient temperature and the state of the fuel supply system. Here it is critically important to use the gas pedal and the pump lever.
With a cold start, it is necessary to enrich the mixture by blocking the air flap. To do this, a “suction” lever is used, which is usually located on the instrument panel or under the torpedo. Pulling the sucker closes the air access, creating a thinning that pulls more gasoline through the jellyplates. Without this procedure, it is almost impossible to start a cold carburetor engine.
⚠️ Warning: Do not overdo it with the suction. If you pull it too hard or pump the gas pedal for a long time, you can "fill" the spark plugs with gasoline, after which the engine will stop starting before they dry.
If the engine is heated, the use of a suction pump is not required and even harmful. In this case, the mixture should be normal and the additional enrichment will lead to fuel overrun and unstable operation. Also on carburetor cars often there is a problem of "gasting" - a sharp press on the accelerator pedal, which is unacceptable on the injector, but on old carburetors sometimes helps to speed up the supply of gasoline to the cylinders at the first start.
Specifics of starting a diesel engine
Diesel engines ignite fuel through high compression, not from a spark of a candle. However, high air temperature is required to ignite diesel fuel in a cold cylinder. For preheating combustion chambers are used lamp-lightwhich are a key element of the diesel cold start system.
The process of starting a diesel engine requires a mandatory wait for the heating of candles. When the key is turned to the first position on the dashboard, a spiral indicator lights up. While it is burning, candles are heated. Turn the key to the starter position is possible only after the indicator goes out. Ignoring this rule in the cold season is guaranteed to lead to an unsuccessful launch.
Modern Common Rail diesel systems are characterized by very quiet operation and high injection pressure. They are more sensitive to fuel quality and battery status. In winter, the use of seasonal fuel and serviceable incandescent candles is critically important for diesel engines, since parafinizing the diesel fuel at low temperatures makes it impossible to start without special additives or heating the tank.
Why does the diesel smoke when it starts?
Black smoke when starting a diesel engine often indicates incomplete combustion of fuel due to incorrectly exposed angle of injection advance or malfunction of nozzles. White smoke may indicate antifreeze entering cylinders or condensate in the exhaust system, which is normal for warming up.
What to do if the battery is drained
The most common cause of startup problems is a weak battery charge. When you turn the key, the starter consumes a huge current (up to 200-300 Amps). If the battery is discharged, the starter will either turn the engine very slowly (“half-power”), or only the characteristic click of the retracting relay will be heard, and the lights on the panel will go out.
In this situation, there are several proven ways to revive the car. The most reliable is the “lighting” from another car using the starting wires. It is important to observe the polarity of the connection, so as not to disable the electronics of both cars. Portable launchers (boosters) can also be used, which are compact and efficient.
For cars with a manual transmission, it is possible to start “from the pusher”. This method is based on the crankshaft rotation due to the movement of the wheels. However, it requires caution: to roll a car with the gear on and a sharp release of the clutch is necessary only with confidence in the safety of maneuver and the serviceability of the timing (the belt may not withstand the jerk).
| Launch method | Equipment required | Risks. | Efficiency |
|---|---|---|---|
| Lighting | Start wires, donor. | Tension surge, sparks | Tall. |
| Booster (Power Bank) | Launcher | Booster's grade. | Tall. |
| With a pusher | Aides or bias | Grip belt break, road accident | Medium |
| Charging from the grid | Stationary ZU, socket | It takes time (hours) | Maximum |
Starting the engine in the winter season
The winter start is a stress test for all vehicle systems. Low temperatures thicken the engine oil, increasing the resistance to the rotation of the crankshaft, and reduce the chemical activity of the battery. In such conditions, the engine may not start even with serviceable candles and fuel, if you do not follow a special algorithm of actions.
Experienced drivers use the method of “waking up” the battery before starting. To do this, you need to turn on the high beam headlights for 10-15 seconds. This triggers a chemical reaction in the battery electrolyte, slightly heating it and increasing the current output. After that, you can try to start the engine, having previously squeezed the clutch to turn off the gearbox and it was easier for the starter to turn only the engine itself.
If the engine didn’t catch on the first try, don’t panic. Let the starter rest, repeat the procedure of “heating” the battery with headlights and try again. In severe frosts, it may take 3-5 attempts. The main thing is not to “set” the battery in zero, otherwise the electrolyte may freeze, which will lead to the destruction of the plates and battery housing.
⚠️ Warning: Never try to start the engine if the oil level in the engine is critically low or the oil is frozen. The crankshaft "on dry" or on thick oil is guaranteed to lead to bullying liners and overhaul.
The main secret of the winter launch is a heated battery (headlights), squeezed clutch and lack of rush between launch attempts.
Frequent Startup Errors and Their Consequences
Many drivers, especially those with little experience, make systematic mistakes that shorten the life of the engine. One of the most common is a long scrolling starter in the hope that the engine will "grab." This leads to overheating of the starter windings and a deep discharge of the battery, after which it becomes even more difficult to start the car.
Another mistake is to ignore the sounds of the engine immediately after starting. If you hear a knock, whistle or see an oil pressure lamp burning, you must immediately turn off the engine. The operation of the engine with low oil pressure or faulty timing in the first seconds can cause irreparable damage, which will cost much more than a tow truck.
Also, do not gas immediately after a cold start. The oil pump takes 2 to 10 seconds to pump the oil through all channels of the lubrication system and create a protective film on the rubbing vapors. A sharp increase in speed at this point works for wear, as engine parts experience oil starvation.
Diagnostics of problems if the engine does not start
If all attempts to start the engine were unsuccessful, it is necessary to conduct an initial diagnosis to understand the cause. Problems are usually divided into three categories: no spark, no fuel, or no compression. It is difficult to check for compression on your own, but the first two causes can often be identified by indirect signs.
If the starter spins cheerfully, but the engine is silent, turn one of the spark plugs and check its condition. If it is wet and smells of gasoline, then the fuel is supplied, but there is no spark or it is weak. If the candle is dry, it is a problem in the fuel supply system (pump, filter, injectors) or in the control system (crankshaft sensor).
What to do if the spark plugs are flooded?
If the candles are filled with gasoline, they must be dried. In the field, you can twist candles, wipe them with rags and warm them with a hairdryer or on fire (with caution). Also helps the “purging” mode: squeeze the gas pedal into the floor (on the injector this blocks the fuel supply) and spin the starter for 10-15 seconds so that the cylinders are ventilated.
Can I start the engine with a faulty starter?
Start the engine with a faulty starter can only be alternative methods: from the pusher (for manual transmission) or towing. If the starter is jammed, launch attempts can lead to a break in the flywheel crown. In case of breakage of the starter on automatic transmission options are few - it is necessary to replace the unit or repair.
Why does the engine start and immediately stop?
Most often, this indicates a malfunction of the idle regulator, the throttle position sensor or the sucker of unaccounted air. The reason may also be the low fuel pressure, which drops immediately after the pump stops operating in the start-up mode.
How often do you need to change the candles for a confident start?
The resource of spark plugs depends on their type. Ordinary nickel candles serve about 20-30 thousand km, platinum - up to 60 thousand, and iridium - up to 100 thousand km. However, in conditions of frequent short trips and winter launches, the resource is reduced, and it is recommended to change them on mileage or when ignition passes appear.