VW and Audi FSI Cam Follower Defect

A Common Issue with FSI High-Pressure Fuel Pumps and Camshafts

If you are experiencing trouble with your VW or Audi, it could be an issue with your cam follower. We are noticing that in specific models of Audi and VW vehicles, the cam follower is wearing down. If the tappet gets completely worn through, it could result in a failure of the high-pressure fuel pump. The issue will sometimes even cause damage to the camshaft. Unfortunately, this happens frequently, and we have done quite a few repairs in the shop for this issue.

Which VW and Audi Models are Affected?

The defect with the tappet seems only to be an issue with certain older VW and Audi models with high-pressure fuel pumps. If you own an older model Volkswagon or an Audi that is a 2.0L Turbo, a Direct-injection, TSI, TFSI, or a TDI, you could experience this issue.

How and Why Does the Cam Follower Failure Happen?

There is a mechanical failure occurring in these VW and Audi models where the tappet is getting worn through. As the tappet wears down, metal pieces can break off and get lodged in the fuel pump, causing significant damage and even failure. If the issue is caught in time, you may only need to replace the cam follower itself. However, if not discovered soon enough, the damage could be irreparable, requiring a replacement of the entire fuel pump. In some cases, the cam lobe, or camshaft, may also sustain enough damage that it needs replacing. If this happens, the cost of the repairs can increase significantly.

So why is this happening? Unfortunately, there is no sure answer. The cam follower serves as a barrier between the high-pressure fuel pump and the camshaft that drives the pump. Over time, the cam follower in specific models will start to wear down until there is a hole. As it wears, small pieces and particles can break off and damage the fuel pump as well as the camshaft. Some say the issue occurs as a result of fuel pump modifications, and others believe it is related to the frequency of oil changes and the quality of oil used. Though, neither of these are certain.

Signs and Symptoms of a Failure with FSI High-Pressure Fuel Pumps

There are a few different signs that could indicate that your vehicle’s cam follower has worn down:

• Check engine light
• Runnability issues
• Loud or low-pitched ticking sounds
• High-pitched knocking sounds

Fault Codes

Some fault codes that could also indicate a worn tappet:

• A mechanical malfunction with the fuel pressure regulator valve
• Low pressure in the fuel rail
• Malfunction in the fuel measuring system

Other Affected Vehicle Models

Though issues with the cam follower wearing down seem to happen mostly in VW and Audi vehicles, we have seen it occur in BMWs as well. If you are unsure if your car model falls into the category of those experiencing this issue, a quick inspection of the tappet could help determine whether your vehicle will be affected or not.

How to Avoid a Failure

As there is no sure answer for what is causing this to happen, the best way to avoid failure is to keep up with maintenance and have the cam follower inspected regularly. If you are a DIYer, you can pull the fuel pump and check the tappet for signs of wear, which should be a clear indicator. You can also scan the car to see what fault codes you have. However, a lack of fault codes does not necessarily mean the tappet isn’t the issue. The only way to be sure is to either check the tappet yourself or bring the car into the shop for an inspection.

How Steve’s Imports Can Help

Steve’s Imports has been providing quality service and repairs to the Portland area for over 45 years. Built from the ground up by Steve himself, we treat everyone like family and understand that your car is more than just a machine to get you from point A to point B – it’s a relationship. Our team works hard and is determined to provide every customer with the best experience possible. If you are having issues with your vehicle, give us a call or stop on by our repair shop today!