The situation when your Lada Granta ceases to react to the turn of the key in the ignition lock, always takes you by surprise. Especially annoying when the starter cheerfully scrolling the crankshaft, from under the panel hears the characteristic buzz of the fuel pump, and the engine is silent like a fish. At this point, most drivers fall into a stupor, as the usual methods of “warming up” do not work, and the car simply refuses to perform its main function.
Such symptoms indicate that the start chain is intact: electricity reaches the starter, fuel enters the ramp. The problem lies deeper, in violation of one of the conditions of ignition of the fuel-air mixture. This may be the absence of a spark, a malfunction in the electronics or a mechanical malfunction of the gas distribution units. Understanding the physics of the process will help you quickly localize the fault and not do stupid things in trying to start the car with a pusher on the machine.
In this article, we will discuss the algorithm for owners. Lada Granta.Those who are facing a similar problem. We will go from simple checks available to everyone to more complex diagnostic procedures that require a minimal set of tools. It is important to act consistently so as not to change the correct details at random.
Primary diagnostics and inspection of security systems
Before climbing under the hood with a screwdriver, it is necessary to exclude the banal, but common reasons for engine locking. A modern car is a complex electronic complex, and sometimes it just “gluts” or is blocked by protection systems. First of all, pay attention to the dashboard: is the indicator on? Check Engine When the ignition is on? If the light bulb does not light up, it may be the problem in the ECU itself or the wiring, but most often it is the immobilizer.
8-valve motors often face a situation when they forget to conduct the key training procedure. If you use a new key or just reset the settings, the system may not see the tag and block the spark from feeding. It is also worth checking the fuses responsible for injection and ignition. Their burnout can occur due to voltage surges or short circuit in the circuit.
⚠️ Warning: If the immobilizer lamp on the dashboard flashes quickly or burns constantly after turning the key, the system blocks the start. In this case, the starter will spin, the gas pump will pump, but there will be no spark.
Another important point is the quality of the fuel. If you refueled at a questionable gas station the day before, the tank could get substandard gasoline or water. Water is heavier than gasoline, it settles to the bottom and first of all gets into the fuel intake, because of which the engine stalls and does not start. Also, do not discount the discharged battery: the starter can spin sluggishly, and the voltage for a powerful spark is not enough to ignite the coil, although the pump is buzzing.
No spark: check of the ignition system
If the starter is confidently spinning, and gasoline is supplied to the cylinders, then spark formation becomes the next critical point. Without a powerful spark, ignition of the mixture is impossible. Nana VAZ-2190 and VAZ-2191 The ignition system can be both with a module and with individual coils (depending on the year of release and the engine). Diagnosis begins with a visual inspection of high-voltage wires and coils for breakdowns and cracks.
The easiest way to check is to twist a candle, put a wire on it (or press a coil), put a metal part on the “mass” (engine) and ask the assistant to spin the starter. The spark should be bright blue and skip between the electrodes. If the spark is weak, reddish or not at all, the problem may lie in the Crankshaft position sensor (DPC). This is Granta’s weak link: when it malfunctions, the ECU simply does not know when to supply spark and fuel.
- 🔥 Check the gap between the DPC and the gear pulley - it should be 0.5-1.5 mm.
- 🔥 Check the sensor chip: often the wires break at the very entrance to the connector.
- 🔥 Make sure the integrity of the high-voltage wires, especially in wet weather.
It often happens that the externally serviceable ignition coil fails under load. On Grants with an 8-valve engine, the ignition module is an consumable material that loses its properties over time. If there is a spark, but weak, or disappears when the engine is heated, the module is better to replace. It is also worth checking the presence of a “mass” on the engine: oxidized contacts can block the operation of the entire system.
Always have a spare DPCV and candle key in the glove compartment - these two details most often cause the engine to suddenly stop on the way.
Problems with fuel supply and pressure in the ramp
The fact that you hear the hum of the gas pump when the ignition is turned on does not guarantee that gasoline enters the cylinders at the right pressure. The pump can buzz, working "idle" if the gas receiver mesh in the tank is clogged or if the pump itself is worn out and does not create the necessary pressure in the ramp. Normal pressure for Lada Granta It should be about 3.6-3.8 atmosphere (bar) at idling.
You can check the pressure using a pressure gauge connected to the fuel ramp connection. If there is no pressure gauge, you can gently disconnect the lead hose (observing safety precautions!) and spin the starter: gasoline should beat with a powerful jet, and not ooze. A frequent cause of pressure drop are current nozzles: they do not hold the pressure after the engine stops, and when starting the mixture is overenriched, which “pours” the candles.
| Symptoms. | Probable cause | Method of verification |
|---|---|---|
| Pump buzzing quietly | Pump wear or clogged filter | Pressure measurement at the ramp |
| Pressure drops fast. | No nozzles or RDT. | Visual inspection after the stop |
| No pressure at all. | Chain break or pump death | Pump contact vertebrae |
Another hidden enemy is the fuel pressure regulator (RDT). If its diaphragm is torn, gasoline through a vacuum tube enters the intake manifold, enriching the mixture to a state where ignition becomes impossible. You can check this by clamping the back: if the engine begins to grasp, then the RDT or the pump cannot cope. Also, do not forget about the fine-cleaning fuel filter, which on Grant is located under the bottom of the car and requires periodic replacement.
⚠️ Warning: When checking the fuel system, observe fire safety! Gasoline is easily flammable, especially in pairs. Do not smoke and rule out sparkling near the open ramp.
How to blow out the fuel system without removing the tank?
If the filter is clogged, you can try to temporarily run the fuel bypassing it, connecting the supply and draining highways with a piece of hose. This will help to get to the service, but you can not ride for a long time - nozzles can get clogged with rust.
Mechanical malfunctions of the engine and HRM
If the electricity and fuel are all right, and Grant still does not start, it is worth thinking about the mechanics. The worst dream of the owner of the front-wheel drive VAZ is the break of the belt of the GM. On 8-valve motors, when the valve breaks, it usually does not bend, but the engine stops working, since the gas distribution phases are disrupted. On the 16-valve versions, the situation is worse: the probability of flexing the valves and meeting them with the pistons is high.
You can check the integrity of the belt by removing the plastic protective cover. If the belt is intact, but the engine spins the starter too easily and with a characteristic whistling sound, this may indicate a lack of compression in the cylinders. Compression is the pressure created by the piston when the mixture is compressed. If it is below 8-9 atmospheres, the engine may not start. Causes of low compression: corrosion of valves, piston rings or breakdown of the gasket of the GBC.
- ⚙️ Check the GRM tags: phases may have lost when replacing the belt.
- ⚙️ Measure compression with a compressometer through candle holes.
- ⚙️ Look at the candles: if they are wet and black, it is possible that the valve is burned.
It is also worth mentioning the sucking of unaccounted air. If there is a hole somewhere in the inlet tract (for example, a throttle duct cracked or a receiver gasket pierced) the mixture becomes too poor. The engine can catch, but immediately stop. You can find the pump by spraying the “Quick Start” or carburetor cleaner at the joints of the pipes of the person working (if you can start) or trying to start the engine. If the speed changes, you find a hole.
☑️ Diagnostics of mechanics
The influence of sensors and electronic control unit
The brains of the car. ECU (Janus, M74, M75) - make a decision on launch based on the readings of many sensors. If one of them lies or is silent, the control unit can go into emergency mode or simply block the launch. In addition to the above mentioned CPI, it is critically important. Throttle position sensor (DPD) and Idle control (RX).
If the RX is contaminated or faulty, it cannot open the channel to supply air when starting, and the engine "chokes." Cleaning the THC and throttle is a procedure that should be carried out regularly. It is also worth paying attention to the DMRV (mass air flow sensor). When it fails, the mixture is formed incorrectly, but usually the engine still starts and operates unstablely, although in rare cases the start can be completely blocked.
Errors can be considered using the ELM327 diagnostic scanner or specialized equipment. The error code will indicate the direction of the search. For example, the error “Ignition skips” may indicate a coil or candle, and the error “Oxygen sensor” rarely blocks the start, but impairs the operation of the motor. It is important to distinguish a real breakdown from the “glitch” of electronics: sometimes it helps to simply reset the battery terminal for 10-15 minutes.
Resetting ECU errors and adaptations by shutting down the battery often helps if the problem is caused by a software failure, but will not eliminate the mechanical breakdown.
Seasonal factors and quality of fuels
Just like any car, the Grant is sensitive to the time of year. In winter, a common reason that the starter spins, but the car does not start, is condensation in the fuel system or freezing of water in the muffler. Water trapped in the tank freezes in the smelter or filter, blocking the supply of gasoline. In this case, even a good pump will not be able to pump fuel.
In summer, the problem may lie in the overheating of the fuel pump or a steam stopper in the highway. If the tank is almost empty and it is hot outside, gasoline can boil in the pipelines and the pump will pump steam rather than liquid. Also in the heat, the evaporation of some fuel grades worsens, which makes it difficult to form the correct mixture during cold start-up.
The quality of the oil also plays a role. Too thick oil in winter creates a huge resistance to the crankshaft. The starter is spinning, but the rpm to create a normal compression and spark is not enough. Using oils with inadequate viscosity (e.g. 10W-40 in winter in Siberia) can lead to the fact that the machine simply does not start, although formally all systems are working.
What if Granta is dead in a puddle?
If you have passed a deep puddle and the car stalled, do not try to start it! Water could get into the cylinders through an air filter (hydro-impact). Re-starting will lead to the destruction of the rods and the cylinder block. You need to remove the air filter, check it for wetness, twist the candles and scroll the engine with a starter to knock out the water. Only when the water is gone can you try the launch.
Can I get Grant off the pusher?
The manual transmission (MHC) on the Grant can be tried to start from the pusher if the problem is a discharged battery or a weak spark. However, if the cause is a glitch in the GRM or the absence of compression, pushing is useless and even harmful. On cars with automatic transmission (Jatco), starting from a pusher is impossible and threatens to destroy the gearbox.
Why do candles fill at launch?
Candles pour gasoline if the mixture is too rich or there is no spark. Frequent causes: a weak battery (few sparks), faulty candles (large gap or soot), air suction (ECU pours a lot of fuel) or low compression. You need to twist the candles, dry them (calcinate or blow), check the spark and try to start with an open throttle (cylinder purge mode).
How to check the gas pump without a pressure gauge?
Remove the chip from the fuel ramp (carefully, putting pressure) or the supply hose. Turn on the ignition: the pump should beep and give out a jet of fuel. If the jet is sluggish, the pump dies or the filter is clogged. If the pump is buzzing, but there is no fuel - a problem in the pump grid in the tank or the supply hose is interrupted. You can also listen to the pump: it should buzz smoothly, without howling and coding.