The failure of this unit is often a surprise to the owner, as symptoms may masquerade as problems with the fuel system or sensors. If you feel that the engine is triplet, loses traction or fuel consumption has risen unreasonably, the first thing to check is the ignition system. Do not postpone the diagnosis, since the engine in the ignition pass mode can lead to failure of the catalytic converter, the replacement of which is many times more expensive than the new coil.
How does the 1.6 MPI ignition system work?
The ignition system on the 1.6 MPI engines (motor code BSF, BSE, CCSA) is built on the principle of "coil on a spark plug". That means that quilt It is installed directly on a high-voltage spark plug, excluding long high-voltage wires that often broke through the insulation on older cars. Each cylinder has its own voltage transformer controlled by an electronic motor unit (ECU).
EBU's signaling ignition module, which converts the low voltage of the onboard network (12 volts) into a high-voltage pulse (up to 30-40 kV). This pulse punches a spark gap on the spark plug, igniting the fuel-air mixture. The peculiarity of this design is that the coil is in conditions of extreme thermal influence, since it is tightly pressed against the head of the cylinder block.
Constant overheating is the main enemy of plastic housing and internal insulation. Over time, the dielectric properties of the material deteriorate, leading to current leakage.
It is important to understand that on a 1.6 MPI engine, the coils often fail in pairs or tend to degrade under high loads, for example, during trailer towing or sharp accelerations.
The main signs of a coil failure
The problem can be determined both by hearing and by the behavior of the car. The most obvious symptom is the uneven operation of the engine at idle speeds. You will feel a strong vibration of the steering wheel and body, and the tachometer needle can begin to swim. In this mode, the cylinder operating in the ignition pass mode does not contribute to power, but continues to consume fuel.
If you notice that the car loses dynamics during acceleration, and the engine speeds โfailโ, this is a sure sign that one of the coils has stopped giving enough voltage.
In some cases, with critical wear, the effect of "floating" turns or even spontaneous stop of the engine at traffic lights can be observed.
- ๐ The engine works unstable, vibrates strongly at idle turns.
- โก There is a smell of unburned fuel from the exhaust pipe.
- ๐ด Check Engine indicator on the dashboard.
- โฝ Significant increase in fuel consumption without changing driving style.
- ๐๏ธ Loss of power and difficulty in abrupt acceleration.
Diagnostics and error codes
To accurately determine the faulty element, you need to connect the diagnostic scanner to the OBD-II connector. The engine ECU records the ignition gaps and issues the corresponding error codes. Without a scanner, you can only assume a problem based on external signs, but this does not guarantee the accuracy of the repair.
The most common error codes for this model are related to ignition skips in specific cylinders: P0301 1st cylinder, P0302 2nd cylinder, P0303 (3rd cylinder) or P0304 4th cylinder. There may also be errors in the coil control circuit, for example, P0351 - malfunction of the circuit of the ignition coil A.
โ ๏ธ Note: If you have a Check Engine on fire and the error code flashes, you must immediately stop moving. A blink indicates that a malfunction can cause serious damage to the catalyst due to unburned fuel entering the exhaust system.
Sometimes the error may not be caused by the coil itself, but by a spark plug or high-voltage contact inside the pad. Therefore, when replacing the coil, it is strongly recommended to check the condition of the spark plugs.
- Engine troubles
- Power Loss
- Check Engine light on
- Increased consumption
Manufacturer's choice: original or analogue
In the market of spare parts there are many options for coils for ล koda Octavia A5. The original part (VAG) is usually marked with the number 036905115B or its modifications. It provides perfect compatibility and durability, but the cost of the original components can be quite high.
Popular manufacturers of quality analogues include Bosch, NGK and Denso. These brands are often suppliers to the conveyor, so their products are not inferior to the original in quality. However, there are many cheap fakes on the market that can fail after a couple of thousand kilometers of mileage.
When choosing an analogue, always check the marking and presence of protective holograms on the package. Cheap Chinese copies often have the wrong geometry of the body, which prevents tight installation in the shoe.
Donโt skimp on the ignition system, as the cost of a new coil is not comparable to the cost of repairing the engine or replacing the catalyst in the future.
| Brand | Type | Approximate price | Service life |
|---|---|---|---|
| Original VAG | Original | High | 100,000+ km |
| Bosch | High-quality analogue | Average | 80,000 - 100,000 km |
| NGK | High-quality analogue | Average | 80,000 - 100,000 km |
| Unipart / Meyle | Budget analogue | Low | 40,000 - 60,000 km |
Why is it important to change the coils with a set?
If one coil fails, it often means that the others are in a similar state of wear. Replacing only one can lead to the fact that after a month you will again have to remove the decorative cover of the engine and change the second part, spending time twice.
Step-by-step replacement instructions
Replacement of the ignition coil on the 1.6 MPI engine is a procedure that can be performed independently in garage conditions. You will need the keys on the 10, 8 (or head), as well as a new coil and, preferably, silicone lubricant for contacts.
First, you need to turn off the battery to avoid short circuits when working with electricity. Then remove the decorative plastic engine cover by simply pulling it up.
Find the faulty coil by cylinder number (according to the error code) or by the method of exclusion. Disconnect the electrical connector by pressing the lock, and unscrew the fastening bolt.
โ๏ธ Preparing for replacement
Remove the old coil. Pay attention to the condition of the rubber seal and the inside of the pad - moisture or oil often accumulates there, which can cause repeated breakdown.
Before installing a new part, be sure to clean the pad from contamination and treat the contacts with a thin layer of dielectric lubricant. This will prevent oxidation and improve signal transmission.
โ ๏ธ Warning: When installing a new coil, make sure it sits down to the point in the spark plug. If it hangs in the air, a spark can pierce the body, causing new problems.
Before you screw the bolt of the coil attachment, check its length. If you confuse bolts from other nodes, a bolt too long can damage the insulation of the coil inside, which will cause it to instantly fail.
Typical maintenance errors
Many owners Octavia A5 They make the mistake of trying to โcheckโ the coil by moving it to another cylinder without diagnosis. Yes, this helps localize the problem, but if you just swap the coils without cleaning the contacts, you can transfer dirt or moisture to a serviceable cylinder.
Another common problem is the use of low-quality spark plugs. If the spark plug has an incorrect gap or a low-quality electrode, the coil will work in overload mode and burn out faster.
You can also not ignore the state of high-voltage wires if they are in your modification, although there are no 1.6 MPI, it is important to check the integrity of the coil connector itself.
Regular replacement of spark plugs and checking the condition of the coils every 60,000 km is the most effective way to prolong the life of the ignition system and avoid sudden breakage on the road.
Impact on fuel consumption and ecology
A faulty ignition coil directly affects the efficiency of fuel combustion. When the spark is weak or absent, the gasoline does not burn completely in the cylinder and flies into the exhaust pipe. This not only increases the cost, but also pollutes the environment.
Exhaust gases with high hydrocarbon content can cause the lambda probe and catalyst to fail. Replacing these components is expensive and takes time.
Timely elimination of ignition passes will return the vehicle passport performance and efficiency, and will also allow you to pass the inspection without problems in the environmental class.
Can I drive with a faulty coil?
Technically, you can get to the service, but it is risky. Prolonged operation of the engine in the "troeny" mode can lead to flare-up of valves or damage to the piston group due to overheating.
Prevention and operating tips
To keep the coils as long as possible, it is important to monitor the condition of the engine as a whole. Oil leaks from the valve cover - a frequent problem on the Octavia A5And the oil, getting into the shoe coils, breaks the rubber and insulation.
Regularly inspect rubber seals on the coils. If they are stained or broken, they should be replaced. Also use only high-quality fuel, as impurities can clog the nozzles, putting a strain on the ignition system.
If you live in a high-humidity region, use silicone grease for contacts with each spark plug replacement. This will create a protective barrier against moisture and oxidation.
FAQ: Frequently asked questions
Can I drive if one of the coils is not working?
Technically, the car will go, but it is not recommended. The operation of the engine on three cylinders creates increased vibration, which can damage the engine cushions, and unburned fuel will quickly kill the catalyst.
How often should I change the coils to 1.6 MPI?
The original coils are designed for a life of about 100-120 thousand kilometers, but in practice they often fail earlier, especially when using low-quality spark plugs or oil.
Why does the new coil immediately fail?
Most often the reason is a faulty ECU, short circuit in wiring or installation of a low-quality spark plug, which overloads a new part.
Do I need to reset errors after replacement?
Yes, after replacing the faulty coil, you need to connect the scanner and erase the error codes from the ECU memory, otherwise the Check Engine indicator may continue to burn.
Which spark plugs are best placed with the coils?
It is recommended to use the original VAG spark plugs or quality analogues from NGK/Bosch with the correct potassium number and the gap indicated in the service book.