A car lifetime in fast-forward mode: 100th Audi Quality Assurance INKA test

12 years in just 19 weeks: Audi Quality Assurance has conducted its 100th INKA test – on an Audi A4. The Ingolstadt corrosion and aging test is one of the toughest assessments a car has to go through at Audi. It simulates the challenges of 12 years of a car’s lifetime in a span of just 19 weeks. Quality Assurance uses this method to verify an Audi's effective corrosion protection and durability.

In the course of performing 100 INKA tests, Audi Quality Assurance has completed a total of 322,500 testing hours, covered more than one million kilometers and driven through 2,800 mud tests and 1,900 salt tests. Sylvia Droll, Head of Materials Engineering: “Audi stands for superior build quality, high-quality material appearance and high reliability – even many years after a car is first registered. The INKA test is an essential tool for assessing the quality of our models and for further optimizing our production methods.”

The endurance test covers five phases. First the car is misted with salt in a climatic chamber at 35 degrees Celsius. Next it is exposed to a tropical climate of up to 50 degrees Celsius and maximum air humidity of 100 percent. In phase three, 80 halogen metal vapor lamps, each with an output of 1,200 watts, heat the body to a maximum of 90 degrees Celsius. In the process, the colors in the interior must not fade and the materials must not become brittle. 

The fourth phase simulates winter-like conditions at the polar circle. At minus 35 degrees Celsius, a four-post hydropulse machine rocks the car to simulate the body torsion and strain on parts of the vehicle and engine mounts that cars endure on rough roads. In parallel – phase five – test drivers repeatedly drive through specially prepared routes on the open testing grounds. 

A total of 12,000 kilometers are traveled with each model, including driving through saltwater and mud. At the end of the test, the quality inspectors dissect the entire car into around 600 individual parts and check these for weak points.

Audi Quality Assurance conducted the first INKA tests in 2002. Technical Development has been assessing pre-series cars using the same test method for 40 years now.