If you have been searching around Craigslist cars for a used vehicle, you may have noticed that a few vehicles that you look at have the “service engine soon” or a “check engine soon” light illuminating. When the check engine light is on, this can mean a number of things and is an indication that the vehicle made need repair. You should not automatically discredit Craigslist used cars that have a check engine light on.
The check engine light is linked to the vehicles onboard diagnostic system. A vehicle’s onboard diagnostic system or OBD creates a trouble code and stores it in the engine’s computer. This trouble code can be retrieved by connecting an OBD scanner to the vehicles OBD Port. There are generally two different types of connectors that are used with the onboard diagnostic system. The first type a connector is for vehicles that were manufactured prior to 1996. This type of connector is usually square and is typically located under the driver’s side dashboard. After 1996, the OBD II system was created and requires a different type of adapter.
When it comes to purchasing a used vehicle on Craigslist that has a check engine light on, the first thing that you should do is test drive the vehicle and stopped by a local parts store such as Advance Auto Parts were AutoZone. Both locations perform a free OBD scan on your vehicle and they actually pull the codes present in the computer. Sometimes, you can actually determine what is wrong with the vehicle by looking at its code. For instance, if the vehicles scan reveals an oxygen sensor code, there is a chance that the problem is a faulty oxygen sensor. You must be careful when using this as a diagnostic tool because sometimes another factor may cause a sensor to send a trouble code. The only sure way to determine what is wrong with the vehicle is to bring it to a mechanic and have it diagnosed. I once purchased a vehicle with a mass airflow sensor code and end it up replacing several hundred dollars in parts, only to find out that the vehicle had a bad computer. Do not rely on an onboard diagnostic code to tell you what is wrong with a vehicle. The code that you pull can assist you in making a decision as to whether or not to purchase a vehicle but should not be considered a reliable means of diagnosing a vehicle.
It is important to remember, in most states a vehicle that is newer than a 1996 will not pass inspection with a check engine light on. The problem must first be remedied before you are able to have your car inspected and passed. This should be an important consideration when purchasing Craigslist used cars because it could prevent you from driving the vehicle immediately. Craigslist cars are a great way to save money when purchasing a used vehicle. Be sure to investigate a check engine light prior to buying your next vehicle.