Certain legal restrictions apply when it comes to looking for an old car.
For obvious privacy reasons, you won’t be able to find out the exact location of the vehicle or the details of the current owner.
Even companies offering paid private background checks must observe GDPR regulations - and therefore will not be able to release any specific identifying information about the vehicle’s owner.
If you do somehow discover personal details about the current owner of your old car, you should refrain from contacting them. This could make them feel uncomfortable (or as if they’ve had their privacy compromised).