Shaking and not starting?

If your 2008 Volkswagen TDI stopped while driving and now shakes violently when attempting to start, there could be several potential issues causing this problem. Here are some common reasons for such symptoms:

Fuel System Issue: A problem with the fuel system, such as a clogged fuel filter, faulty fuel pump, or air in the fuel lines, can lead to improper fuel delivery to the engine, causing the vehicle to stall and shake when trying to start.

Ignition System Problem: Issues with the ignition system, such as a failing ignition coil, spark plugs, or ignition control module, can result in misfires and cause the engine to shake or refuse to start.

Timing Belt or Timing Chain: If the timing belt or timing chain has slipped or broken, the engine's timing will be affected, leading to severe shaking and a no-start condition.

Compression Problem: A loss of compression in one or more cylinders due to a blown head gasket, damaged piston rings, or valve issues can cause the engine to shake violently and prevent it from starting.

Electrical Issues: Faulty sensors, a malfunctioning Engine Control Module (ECM), or other electrical problems can impact the engine's performance and starting.

Air Intake or Exhaust Restriction: A blocked air intake or exhaust system can disrupt proper engine operation and lead to shaking and stalling.

Turbocharger Issue (if equipped): If your TDI model is turbocharged, a malfunctioning turbocharger can cause engine performance problems and stalling.

Given the severity of the symptoms and the complexity of potential causes, it's essential to have the vehicle diagnosed by a qualified mechanic or a Volkswagen dealership. They will use diagnostic equipment to retrieve trouble codes and perform tests to identify the specific problem.

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

and

https://www.2carpros.com/articles/car-not-running-advanced

Please go over this guide and get back to us.