The spark on VAZ 2109 (carburetor) disappears: possible malfunctions and their elimination

The ignition system of the carburetor engine VAZ 2109 is simple enough, therefore it does not have critical malfunctions. And those problems that sometimes happen, without special problems can be fixed independently. In this article we will talk about the reasons why the spark on the VAZ 2109 (carburetor) is gone, and also consider the methods for their elimination.

Symptoms of a malfunction

Malfunctions of the ignition system are manifested by unstable operation of the engine or its complete stop and inability to start. In the first case, the engine significantly reduces power, fuel consumption increases, the color of the exhaust changes, and vibration appears. Such symptoms may indicate that in one of the combustion chambers there is no burning of fuel, or that a spark formed on the electrodes of one or more candles can not ignite it. In the second case, when the engine does not start at all, most likely, there is a malfunction of one of the main elements of the system. It is often leads to the fact that the spark disappears on VAZ 2109 (carburetor).

Carburetor engine ignition system

All the "nine" from the plant are equipped with a contactless ignition system. Constructively it consists of the following elements:

• The ignition switch;
• High voltage coils;
• Commutator;
• The ignition distributor with a Hall sensor;
• Four high-voltage wires;
• Spark plugs.

In the event of a malfunction of any of the first four elements, the ignition system ceases to function and the engine can not be started. You can correct the situation by performing diagnostics and troubleshooting.

How does the ignition system of the carburetor VAZ 2109 work?

To understand why the spark on the VAZ 2109 (carburetor) disappears, let's look at how its ignition system works. Let's start from the very beginning - from the castle. When the driver inserts and turns the key in the ignition lock, the electric current is supplied from the battery to the coil. It performs the function of a transformer, converting the standard 12 V to 25,000-30000 V. From the coil, high-voltage current flows to the ignition distributor, driven by the engine's camshaft, and from it through the high-voltage wires to the candles. The switch participates in this whole process, providing the generation of current pulses of the desired value in the coil, and also stabilizing the voltage in the system.

High voltage wires

So, if you suspected that the spark on the VAZ 2109 (carburetor) is missing, first of all you should check the integrity and fixing of the high-voltage wires. To do this, lift the hood and conduct a visual inspection of the conductors coming from the coil to the ignition distributor, and also from it to the candles. Check if they are securely fastened, whether there is dirt or moisture on their contacts.

To determine if the armored tube is in good condition, you can check them with a car tester included in the ohmmeter mode. The resistance of each of them, depending on the brand and manufacturer, should be from 3.5 to 10 kOhm. If it is higher, you can be sure that the spark on the VAZ 2109 spark was lost for this reason. To change high-voltage wires you need a kit.

Candles

At carburetor VAZ 2109 spark plugs more often than other elements of system fail. This is due to the poor quality of fuel, and the improper setting of the fuel supply, and with the candles themselves. In addition to the fact that there are a lot of fakes in the auto parts market, not every owner of the "nine" bothers with the glow number or gaps between the electrodes prescribed by the manufacturer's recommendations. So it turns out that by buying seemingly new and branded candles, we have an unstable idling or even a trip. In the future these small, seemingly faulty ones can lead to more serious problems.

Ignition VAZ 2109 provides four spark plugs: one per cylinder. They are checked in turn. First one of them is unscrewed, visually inspected for the integrity of the ceramic insulator, the state of the electrodes and the size of the gap between them. If the candle, at first glance, everything is in order, you need to determine its performance. To do this, it is put on the cap of the high-voltage wire and the skirt is attached to the mass. Next, you need to get an assistant and ask him to start the engine. When the starter starts to rotate the crankshaft, a stable spark of blue or blue should jump between the electrodes. If it has a different shade (red, greenish), this may indicate a possible breakdown of the insulator or insufficiently high voltage. If there is no spark at all, most likely the candle has failed. But here you can not exclude other malfunctions. That's why you need to check all the spark plugs. In the case where only one of them does not work, try to replace it with a working one. But if there is no spark on all the candles, the problem needs to be looked for deeper.

Egnition lock

The next step in the diagnosis is to check the ignition switch. For this we need the same car tester, but already included in the voltmeter mode. Connect the probe probe to the "+ B" terminal on the ignition coil, and the negative terminal to ground. Then turn on the ignition and look at the tester's readings. The absence of voltage is evidence that the contact group of the lock is faulty. In this case, the repair (VAZ 2109) provides for its replacement.

Coil

As we have already said, a coil is a transformer that generates a high-voltage current. It has two windings, which are not insured against closure or breakage. If it does not start 2109 (carburetor), the coil check is mandatory. Moreover, it is quite easy to determine its efficiency. For this, when the engine is off, remove the central high-voltage wire from the coil from the ignition distributor cover. It has a protective cap. To it, you need to connect the spark plug and apply it with a skirt to the mass. After this, ask the assistant to turn on the ignition and scroll the starter. If the coil is working, a spark appears between the spark plug electrodes. A defective transformer can not boast of this.

Important: in no case do not hold the candle with your hand or pliers without the insulation of the handles. The voltage produced by the coil reaches several tens of thousands of volts, and even considering the relatively small current, there is a threat of destruction to them. It is also not worth checking the presence of a spark without a candle, i. E. Between the wire and the ground. This will disable the switch.

Distributor

After the coil is checked and the results of the diagnostic show that it is completely in order, go to the ignition distributor (tramp). Disconnect from its cover high-voltage wires and turn off two screws of its fastening. Remove the lid and inspect it for integrity. Pay attention to the condition of the coal contacts and the distributor slider. In the event of a malfunction, the lid (complete) must be replaced.

The Hall sensor serves to transmit control and corrective pulses to the switch, depending on the number of engine revolutions. It is installed inside the ignition distributor, but to check it, it is not necessary to disassemble this element. You will only need a car tester or multimeter, included in the voltmeter mode, as well as a pair of pins.

Find the green and black-and-white wires in the connecting block, which is connected to the distributor. This is the sensor's conclusions. On these wires, pins need to pierce the insulation, and connect the test leads to them. Ask the assistant to slowly turn the engine crankshaft by hand. This can be done either with a screwdriver, pushing the flywheel through the hatch in the clutch housing, or using a key that is slung over the crankshaft pulley nut .

If the Hall sensor is OK, the device will show a voltage jump from 0.4 to 12V when rotating. If it becomes unusable, the device will be "silent." In this case, repair (VAZ 2109) will be limited to replacing the sensor.

Switch

Finally, let's talk about the switch. Its function is the formation of correct electrical pulses in the primary winding of the coil on the basis of the data obtained from the Hall sensor. In addition, it limits the maximum current and voltage in accordance with the parameters of the on-board network.

Check the switch without having special equipment, it is quite difficult. The easiest way is to connect a known good element and check the operation of the ignition system. Some owners of VAZs, taught by bitter experience, often even carry a spare switch with them, and in which case they simply put it in the place of the failed one.