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

2024 Author: Erin Ralphs | [email protected]. Last modified: 2024-02-19 11:42

Failures in the ignition system of carbureted "Samar" are a frequent phenomenon and familiar to most owners of these cars. But they happen, as always, at the most inopportune time. For a novice car enthusiast, the search for a missing spark can drag on for several days, or even weeks. For a person who has ever had to face such a problem, it is a matter of one or two hours.

In this article we will figure out why the spark disappears and what it may be connected with. We will consider the most likely causes of the malfunction, as well as methods for their elimination using the example of the usual "nine".

In preparation

In a situation where the VAZ 2109 (carburetor) does not start, it can be assumed that the matter is either in the power system or in the ignition. But, since we are talking about the latter, we will consider the problems associated with the supply of electric current to candles.

In order to determine that the spark has disappeared on the VAZ 2109 (carburetor), we need an assistant and the following tools:

• voltmeter (multimeter);
• candle key;
• pliers;
• crossscrewdriver.

No spark on VAZ 2109 (carburetor): reasons

Before proceeding with the check, it does not hurt to deal with those nodes that are involved in the sparking process. These include:

• battery;
• ignition lock contact group;
• coil (transformer);
• switch;
• distributor (distributor);
• Hall sensor;
• high voltage wires;
• candles.

Each of these elements can fail, which will inevitably lead to a break in the electrical circuit. If the spark on the VAZ 2109 (carburetor) really disappeared, then it could disappear in any of the sections. In order not to complicate the task of finding it, the initial check should be carried out in two stages: to establish whether there is current at the output from the ignition coil and whether there is a spark on the candles themselves.

Determining the area

If the VAZ 2109 (carburetor) does not start at all, it is better to start checking in the area from the battery to the distributor. So we will understand if the battery, the contact group of the lock, the switch and the coil are working.

Check order:

1. Raise the hood.
2. Disconnect the “cradle” of the central armored wire from the cover of the distributor.
3. Insert a candle into the “cradle”, press it with a “skirt” to the valve cover (unpainted section of the body) and ask the assistant to start the starter. Never hold the candle with bare hands! You will receive an electric shock. Not lethal, but rather annoying. It's better to hold a candlejust dielectric pliers.
4. While the starter is running, look at the interelectrode space. If there is no spark there, the VAZ 2109, of course, will not start.

Now we have to install the defective element in the battery-coil section. It's easy to do.

Battery and ignition lock contact group

If you have established that the spark has disappeared on the VAZ 2109 (carburetor) in the area from the battery to the high-voltage output of the coil, a discharged battery and a faulty ignition switch may be to blame. Let's check if electricity is supplied to the coil. To do this, using a voltmeter (multimeter), with the ignition on, we measure the voltage between the “+ B” terminal of the coil and the “ground”. If it is, its value must be at least 11 V.

Lack of voltage indicates the failure of the contact group. The most common cause of a malfunction is oxidation or burning of the terminals. This problem is eliminated by stripping contacts.

Coil

The VAZ 2109 ignition coil itself rarely fails, but it must be checked. This can be done using a multimeter turned on in ohmmeter mode. We connect one of its probes to the “+B” contact, and the second to the “K” terminal. These are the ends of the primary winding. The resistance value should be 0.4-0.5 ohms.

After that, we check the secondary coil by connecting the probes of the device to the “+ B” terminal and the high-voltage terminal. Here the resistance should be about 4-5 kOhm. Atany other indicators, the ignition coil VAZ 2109 must be replaced.

Switch

The situation is somewhat more complicated with the switch. The thing is, you can't test it yourself. The best solution here is to swap with a known-good device.

Having determined that the spark on the VAZ 2109 (carburetor) has disappeared in the area up to the distributor, we can immediately conclude that the switch is the reason for this. This is the most capricious device in the entire ignition system. It can “burn out” due to the slightest voltage drop caused by a malfunction of the generator, malfunction of candles or high-voltage wires. That is why some experienced Samar drivers carry a spare device with them.

Finding the Spark: Candles

If there is still voltage on the central high-voltage wire, it is necessary to establish whether it is distributed and whether it is supplied to the candles. To do this, you need to determine whether the distributor and the Hall sensor are working, whether the high-voltage wires and the working candles are broken. Let's start from the end.

Remove the first spark plug, place it on the valve cover with the high voltage wire still connected to it, but disconnected from the other spark plugs, and have an assistant try to start the engine with the starter. Visually determine if a spark appears between the electrodes. If it is, screw the spark plug back in and repeat the procedure for each individual cylinder. Be aware of the risk of being electrocuted, use pliers!

If there is no spark on the VAZ 2109 (carburetor) candles, try replacing them with new ones or obviously good ones. The situation has not changed? We continue the diagnosis.

High voltage wires

High-voltage wires, of course, cannot all fail at the same time, but it's still worth checking them. The definition of performance is to measure the resistance of each of them. We disconnect the wires one by one and take measurements. For serviceable conductors, including the central one, the resistance should be in the range of 2.7-9 kOhm. After identifying deviations from these indicators, replace the defective element.

Ignition distributor and Hall sensor

As for the distributor, the most common malfunction is the burning of the contacts located inside the cover. In addition, the slider, which “carries” the voltage, can also fail.

Unscrew the two screws and remove the cover from the distributor. Pay attention to the status of contacts. If they are badly burned, deformed, crumbled - replace the cover. Look at the runner too. It can also burn and warp. Replace it if necessary.

It will not be superfluous to check the so-called "coal". This is a graphite contact of a high-voltage wire. If it is damaged, the voltage stops flowing to the slider. As a result, all four candles are de-energized.

Hall sensor is built into the distributor. You can also check it without removing it with a voltmeter. The probes of the device must be connected togreen and black and white wires from the sensor to the connector. Scrolling the flywheel with a screwdriver (in the window on the clutch housing), read the voltmeter. They should range from 0.4 to 12 V. If this is the case, the sensor is in order. Well, if not, the device needs to be replaced.

Here, in principle, are all the common malfunctions for which the "nine" does not have a spark. VAZ 2109, as you can see, is not such a complicated car in this sense: a little time, a little theory, a simple tool, and your car is back in service!