Volkswagen Audi engine timing chains come in many variations specific to the vehicle but have the same responsibility to keep mechanical synchronization within the engine to ensure smooth operation. The engine in question is a 2.0 CAEB TFSI. Here are some insights:
What is a timing chain? It is a metal chain that wraps around sprockets within the engine that are attached to crankshaft and camshafts to synchronize the stages of intake, compression, combustion, and exhaust for the engine to produce power.
What are symptoms of a bad timing chain? Some may include:
- CEL Light- The check engine light is on and may have timing codes stored in the ECM module.
- Hesitation- Vehicle is having trouble starting or may not start at all.
- Rattling sound- A rattling sound can be heard from the engine with accordance to applying gas.
- Misfire- You may see the CEL light flashing as a sign of misfire. The engine will shake violently too if it's bad enough.
- Oil contamination- Tiny metallic shaving floating inside oil
As one case, a vehicle came in experiencing an extended crank upon start-up; the engine would turn off on it's own or stall. During the diagnostic service, the technician experienced an engine rattling sound. These codes shown below that was extracted from the ECM suggests the engine timing is out of sync.
- P050600 Idle control System RPM Lower than Expected
- P001600 Crankshaft Position-Camshaft Position Correlation Bank 1 Sensor A
- P007000 Ambient Air Temperature Sensor Circuit
- P0300 Random/Multiple Cylinder Misfire Detected
- P0301 Cyl.1 Misfire Detected
- P030200 Cyl.2 Misfire Detected
- P030300 Cyl. 3 Misfire Detected
- P030400 Cyl. 4 Misfire Detected
Upon further investigation, the front bumper was removed to gain access to the front of the engine covers. The front engine timing covers are also removed here to be able to visually inspect the timing chain components without obstruction.
A clear sign of a stretched timing chain can be determined by inspecting the chain tension. In the photo below, we can see the tensioner is fully extended out, trying to apply tension to the chain. This customer was advised to have the timing chain serviced which includes replacing all the tensioners, guides, oil control valve, camshaft magnet, timing cover and other associated parts to make the vehicle run true once more.
After installing the new parts, the timing chain tension no longer protrudes out much as before and has become shortened. This is a good sign that the chain has proper tension and the installation was a success. After the timing covers and the bumper is reinstalled, the technician operated the vehicle on the road to ensure all the customer concerns has been remedied. The vehicle no longer shows any timing codes and is running.
How could this have been prevented? Proper maintenance and care is the key to prolonging internal engine wear. Certain vehicles will come with an inspection window on the timing cover to inspect how stretched the chain is. As the premier Volkswagen Audi repair shop in Brooklyn, our technicians at MINHS Automotive provides this service with our routine oil change. We may not be able to prevent the timing chain from stretching but with proper maintenance and keeping up with the service intervals and oil changes, we can prolong and lessen the chances of it happening.