Repairs May Lead to New Issues

Car repairs can be likened to medical visits. A doctor first diagnoses a problem before recommending treatment. However, if the diagnostic process is flawed, it can result in damage to other parts of the vehicle. This scenario is similar to refurbished electronics, which often fail to match the quality of new devices.

Research in the paper titled "Correlation Analysis of Key Automobile Component Failures" discusses a diagnostic technique for electronic systems known as the “Short Circuit Test Method.” This approach involves intentionally short-circuiting a potentially damaged circuit to pinpoint the issue. Unfortunately, this method can sometimes generate excessive current, risking damage to other electronic components.

Once the fault is identified, repairs are necessary. Many components must be disassembled for effective repair, which can sometimes lead to accidental damage. For example, when taking apart a dashboard, plastic clips might snap. After reassembly, the dashboard could become loose, creating annoying rattling sounds during driving.

Similarly, when cleaning the throttle body, improper handling during disassembly can result in hoses not being reattached correctly, causing engine vibrations, loss of acceleration, or even triggering the check engine light. Many vehicle owners report needing additional repairs due to "damage caused by the repair process," highlighting that fixing one issue can inadvertently lead to others.

Repairs Can Alter Performance

Even when repairs are executed properly, the vehicle may not perform as well as it did originally. Consider the importance of properly tightened screws. Certain parts of a car, like tires and wheel hubs, must be secured with a tool called a torque wrench, which specifies exact tightening measurements.

However, even the most precise torque wrenches come with a margin of error, making it nearly impossible to achieve the factory assembly standard. Additionally, not all repair shops have access to high-quality torque wrenches. If screws are not tightened correctly, they could loosen or break, leading to higher failure rates compared to original components.

This issue extends beyond minor parts; achieving the original performance of crucial components like engines or car bodies post-repair is even more complex. The book "Fundamentals of Automotive Engineering," published by Tsinghua University Press, notes that the reliability of a car diminishes after significant repairs due to varying levels of maintenance equipment and techniques.

Quality of Replacement Parts Matters

Moreover, if repairs are performed at independent shops, the quality of replacement parts can significantly influence failure rates. Original parts are typically sourced directly from manufacturers, ensuring stringent quality control. In contrast, independent repair shops often resort to aftermarket parts, which can vary in quality.

While not all aftermarket components are substandard—some may even meet or exceed original specifications—the inconsistency is concerning. For instance, brake pads must comply with specific thickness and wear standards. Original parts are guaranteed to meet these criteria, while aftermarket alternatives may not. A study by China's National Quality Inspection Bureau found that over 13% of brake pads did not comply with safety standards, increasing the risk of premature failure.

Older Vehicles and Their Fault Rates

Finally, the age of a vehicle plays a crucial role in its likelihood of experiencing faults. The aforementioned study also outlines that a car's failure rate evolves over time, typically categorized into three phases: early failure, random failure, and wear-out failure.

During the random failure phase, the vehicle is generally reliable, with only occasional issues that are easily resolved. However, as the vehicle ages, it enters the wear-out phase, characterized by a noticeable increase in failure rates. Often, when one component fails, it's a sign that other parts are nearing the end of their lifespan, leading to a perception that frequent repairs contribute to an overall decline in the vehicle's reliability.

The first video titled "Car Repair Costs More Than The Car! What Should I Do?" provides insights into the high costs associated with car repairs and what options you have when facing these situations.

The second video, "At What Point Is It Not Worth Fixing Your Car," discusses the critical factors to consider when deciding whether to repair an aging vehicle or explore alternatives.