What to Consider When Buying a Car with Replaced Camshaft and Crankshaft Position Sensors

When considering the purchase of a car that has recently replaced its camshaft and crankshaft position sensors, especially if the vehicle has over 180,000 kilometers and multiple prior owners, you must carefully weigh several factors. This article aims to help you make an informed decision by addressing common issues and suggesting steps to ensure you buy a reliable vehicle.

Understanding the Sensors

Camshaft and crankshaft position sensors are crucial components in modern engine management systems. They are responsible for providing signals to the engine control unit (ECU) to ensure proper combustion. These sensors can develop issues over time, especially in high-mileage vehicles. However, their failure does not automatically indicate significant engine problems.

Common Issues with Replaced Sensors

During a past ownership, your vehicle may have experienced intermittent engine cutouts. These can sometimes be misleadingly diagnosed as crankshaft position sensor problems. Since these sensors are relatively easy to replace and inexpensive, they were likely replaced. However, the issue may have been camshaft sensor related. When a professional diagnosis was conducted, the camshaft sensor was found to be faulty, resolving the issue temporarily.

Buying a High-Mileage Used Car

High-mileage vehicles can pose additional risks, especially when sensors have been replaced. Here's what you should consider:

Don't be overly concerned: With nearly 180,000 kilometers, the vehicle is toward the higher end of high-mileage, but it's not necessarily a cause for alarm if the rest of the vehicle history seems normal. Independent Inspection: If possible, take the car to an independent shop for a thorough inspection. If the seller refuses, it may be a red flag and a sign to proceed with caution. Vehicle History Report: View the vehicle history report as a source of information rather than a definitive health indicator. Use it as a starting point for your investigation.

Exploring Further Diagnostics

Given the recent replacement of these sensors, there are two possibilities:

Sensor Replacement Given a Recent Fix: One of the sensors likely fixed a recent issue, while the other was replaced for insurance purposes. Inadequate Fix: In a misguided attempt to resolve the problem, the sensors were replaced, but the issue still persists. This could indicate a more significant problem, such as worn timing chain components.

Specifically, if a "cam/crank correlation" code is present in the vehicle, the replacement of the sensors did not resolve the underlying issue. In that case, a complete check-up is necessary.

Model Consideration and Driving Habits

For a 2013 model, the mileage at 180,000 kilometers is considerable. However, the age of the vehicle (9 years) needs to be factored in. A Toyota, for instance, might have different reliability expectations based on its history. If the sensors have failed, this could indicate significant engine revolutions, perhaps due to high idle times.

Evaluation of Idle Time

Consider the example of a 2005 Chevrolet Impala with over 130,000 miles. Through educated guesswork and simple math, it was determined the car had 350,000 to 400,000 highway miles in idle time. This time, if the car has run 89,000 miles in 2013, the idle time could be around 2,966 hours, amounting to nearly 145,000 kilometers in idle revolutions.

Using theoretical calculations:

2966 hours of idle time, at 750 RPM, would equal 22,245,000 revolutions. At 60 mph and 1500 RPM, 135,000,000 revolutions would equate to ~90,000 miles.

This indicates a considerable amount of engine revolutions, which could be concerning if done at idle. High idle time could be an indication of significant wear on the camshaft and crankshaft position sensors.

While these findings are interesting, it's important to weigh them against the overall condition of the vehicle. It's possible to make an informed decision by combining this data with personal inspection and expert advice.

Final Thoughts

Despite the concerns raised by the replaced sensors and high mileage, the vehicle could still be a good deal. However, proceed with caution. Take the car to an independent mechanic for a thorough inspection, and carefully consider the history of the vehicle. Remember, the key is to be well-informed and prepared for any potential issues that may arise.