The Volkswagen MK6 GTI 2.0T TSI took the MK5 and made it more appealing. It was better than just a facelift. It took what the MK5 did well and made significant improvements to the car at every corner. The MK6 is still an incredible platform and is more affordable than ever, but they’re becoming older and will need some maintenance. Some common issues are well documented and should be addressed if you plan to pick one up or have just added one to your stable. Today, we’re talking about the MK6 2.0T TSI misfire problems and how you can fix them.
What is a misfire?
Misfires happen when a cylinder does not receive spark for one reason or another and the cylinder does not ‘fire,’ or rather, combust. The air and fuel in the combustion chamber were not ignited due to a lack of spark, so it ‘misfired.’ This is less than ideal and can be the result of one or more faults. In the MK6 2.0T TSI, this is a common issue at higher mileage, especially if your engine is making more power than stock. Not only will a misfire ultimately foul your catalytic converter, but it will cause you to fail vehicle inspections and can ultimately become more than inconvenient. So, it’s important to handle this immediately rather than wait for a more expensive repair down the road and possibly not legally receiving your annual registration.
Why does it happen?
A misfire can happen if the spark plug has fouled, the coil pack is bad, there is excessive carbon buildup on the valves, or the air/fuel mixture is wrong to the point that it will not ignite. In the 2.0T, the usual culprits are either the coil pack or a fouled plug. It can happen either when driving or on a cold start, which signifies two different problems. If your engine experiences misfires on a cold start, it is likely the cause of carbon buildup, meaning you need to walnut blast your intake valves. If it happens while driving at temperature, it is probably either a bad coil, bad plug, or both.
How do I diagnose a misfire?
First, you will see either a blinking or constant check engine light. If your CEL is blinking, DO NOT DRIVE your car. Blinking means the misfire is happening on every cycle, which means you effectively have a non-firing cylinder. If the CEL is constant, it registered a code once or randomly and is alerting you that you have a random misfire. With the Schwaben Scan Tool, you will be able to see the codes, which will read P0301, 2, 3, or 4, depending on which cylinder has the misfire.
To confirm, you should first determine what the cause of the misfire is. If you have P0301, your first cylinder is not firing. This could be one of several reasons we listed above. First, switch the coil pack from CYL1 to CYL2 and see if the misfire code reads P0302. If it does, you have a dead coil pack. If the misfire persists in the first cylinder, you should then try switching the spark plug to CYL2 and check once more. You can usually look at a plug and tell if it is fouled or dead. Black, burnt, buildup signifies carbon and means you likely need a good old fashioned walnut shell blasting, which we offer as a kit with the proper adapter to use with your engine.
If your misfire does not follow either the spark plug or the coil pack when you switch them to another cylinder, you might have other issues. A full scan with the Schwaben Scan Tool should tell you if anything else is happening that shouldn’t be.
How do I fix it?
Likely, the cause is either a bad spark plug or a dead coil pack. With the MK6 2.0T, as with all engines, replacing the spark plug/coil pack is a must. However, you don’t want to replace just one. If one is dead, the others will follow shortly. In the 2.0T TSI, misfire faults are common, especially if your engine has been modified for more power. We suggest that you replace all four at once. Which coil packs you choose, however, is entirely up to you.
What are my coil pack options?
You can always choose to go with the OE Genuine VW/Audi coil packs, which offer the same option you would receive at the dealership, for predictable performance and function as the 2.0T TSI was intended to have. We offer a Genuine VW/Audi option that is considered by many in the enthusiast community to be an ‘upgrade’ to their ignition: the Audi R8 ‘red-top’ coil pack. These are designed for the high-performance R8 engine, so we think they’re more than qualified for use in the compatible 2.0T. For this reason, we use Genuine VW/Audi coil packs in an Assembled by ECS ignition service kit.
Bosch coil packs are similarly designed. They are quite popular for their performance and cost. These also have the ‘red-top’ appearance and are equally qualified, making them one we suggest in another Assembled by ECS ignition service kit.
We also offer a range of other options recommended for rejuvenating your MK6 GTI and eliminating that misfire in our selection of Service Kits that have everything you need to perform this critical service.
With the help of a Schwaben Scan Tool, you should feel confident in your ability to diagnose a misfire issue or any issue that may arise, in your MK6 GTI 2.0T TSI. This is the first weapon to use against any problems you will encounter during your ownership as the car ages. Like any car, the GTI requires attentive maintenance and service. If something happens you aren’t expecting, the Scan Tool will make your job much easier and take the guesswork out of your solution for repairs.
The Assembled by ECS Ignition Service Kit includes new spark plugs and upgraded coil packs designed to ensure that your 2.0T runs as it should for the duration of those parts’ expected life spans and will prevent any weak spark at high boost, which is usually the issue when it comes to misfires in the 2.0T. Along with your ignition service, we recommend you also service the engine oil with LIQUI MOLY and a Hengst filter.
Lastly, if your issue is larger than the coil pack or spark plug, it is more than likely carbon buildup from the direct injection method of fuel delivery. With the Media Blaster kit and our MK6 2.0T TSI nozzle adapter, you can clean your intake ports and valves at home, saving yourself money on the repair and headaches down the road. Make sure your 2.0T doesn’t have carbon buildup and you will be able to enjoy the full power of this impressive turbocharged four-cylinder for years to come.