Many owners jump to a diagnosis so they seem knowledgeable - hoping that a specific request for "just a tune-up" prevents a repair facility from piling services they don't need onto their bill. A better tactic is to describe symptoms as you would with your doctor. It's fine to look at the troubleshooting chart in your owner's manual, but let the expert do the diagnosis.

The more specific and thorough you can be about your vehicle's performance, the more you can help the technician zero in on the problem. Be precise. For example, refer to the driver's side and passenger side (not the left or right side) of the vehicle.

If your vehicle has been worked on recently, be sure to tell the technician. During earlier repairs, wires could have been punctured when electrical circuits were checked. A year or two later, there may be corrosion inside those wires, causing high resistance that results in an engine performance problem.

Ideally, put your observations in writing. If you go into the facility with a written list, that's a good safeguard that you will provide thorough information without forgetting anything.

Sharing information empowers you and the technician. No one expects you to have the technical expertise to define the problem, but your observations are critically important.

You may feel some of your observations are a little silly or irrelevant, but note them anyway. Full disclosure will save the technician time. If you do not share what you know about your vehicle, the best case is that the diagnosis will cost you more; the worst case is that needed repairs will not be made and you could endanger yourself and your passengers.

Next: Problem descriptions that are useful to the technician >>