How To Fix Volkswagen Ignition Coil Failure
A working ignition coil is essential to the successful combustion of your Volkswagen’s engine. The ignition coil looks like a silver tube with a black plastic aperture. It is a transformer that converts low voltage electricity into high voltage, providing the spark plug with the power needed to create a spark to ignite the fuel within the engine. This drives the crankshaft and powers your car. If this part is not working properly, your Volkswagen will not run.
In this article, we will take a look at the ignition coil, learn why it fails, discuss symptoms of failure, and talk about how you can fix a faulty coil.
What causes coil failure?
There are several reasons why your ignition coil may start to fail such as:
- Internal Short Circuits: This is caused by either overheating of the coil, an old coil, or a faulty output stage.
- Faulty Voltage Supply: This is caused by wear or overload on the ignition control unit or output stages, caused by faulty wiring or weak battery.
- Mechanical Damage: This is caused by faulty valve cover gasket, engine oil leaks, or damaged insulation.
- Contact Fault: This is caused by humidity, engine washing, or grit.
Symptoms of Faults or Failure
As the ignition coil directly impacts the performance and effectiveness of your engine, many of the symptoms of faults or failure center around engine performance such as:
- Reduced Fuel Efficiency: While reduced fuel efficiency can point to a number of problems, it can also be caused by your engine compensating for failing ignition coils.
- Stalling or Misfiring: As the ignition coil is responsible for giving the spark plugs the power needed to ignite the fuel in the engine, if these parts are fault then your car is likely to experience regular engine misfires.
- Starting Problems: Similar to the point above, your ignition coils need to be working to ignite the fuel in the first place. Without them working correctly, starting your Volkswagen can become difficult.
- Overheating Engine: When an ignition coil starts to overheat, it typically has a similar effect upon the temperature of the engine itself.
- Vibrating Engine: An engine that is vibrating more than normal can also be a sign of faulty ignition coils.
- Worn Out Spark Plugs: If your spark plugs become worn out quickly or fail quicker than expected, you might have a faulty ignition coil on your hands.
Repairing Faulty Ignition Coils
Repairing or replacing a faulty ignition is quite a mechanically-advanced procedure and should only be undertaken as a DIY project by those with prior mechanical experience or skill. However, the process goes as follows:
1. Visual Inspection
Before undertaking any diagnostics or repairs, you should undertake a visual inspection. Check the engine wiring harness for damage as well as the plug connectors.
2. Check the Voltage Supply
Next, check the voltage supply. To do this, remove the connector from the ignition coil and measure the voltage at the two-pin connecting on the wiring harness side. Next, connect the multimeters red cable to PIN 2 (+) and the black cable to engine ground (-). Switch on the ignition and measure the voltage.
3. Check the Primary Actuation of the Ignition Coil
First, remove the connector from the ignition coil and then connect your diagnostic tester of choice to the measurement module, connecting probe tips to PIN 1 and 2. Detach the plug connectors from the injection valves and start the engine.
4. Removing the Ignition Coil for Testing
Remove the connector from the ignition coil and also remove the high-voltage cable and the fixing screws and pull the ignition coil out vertically.
5. Measure the Resistance
Use a multimeter to check the removed coil. Connect an ohmmeter to the component connector (both PIN 1 and PIN 2) to measure the primary winding.
6. Replace the Ignition Coil
Replace the ignition coil, being careful to ensure the spark plug connector and the high voltage cable are inserted properly. Be sure to insert all the plug connections for both the ignition coil and the injection valve connecters.
7. Clear Fault Memory
Clear all faults before test driving.
8. Test Drive
Undertake a test drive with the diagnostic unit connected. Check the fault memory again.
Complete Automotive Systems
If you’re not mechanically savvy and need your ignition coils replaced, then head on down to Complete Automotive Systems. Servicing those living in and around Beverly Hills, Culver City, Brentwood, Santa Monica, CA, no job is too big or too small for the dedicated team of experts at Complete Automotive Systems.