Under The Hood
HUNTER TAYLOR

Sometimes it seems as though our cars have minds of their own. As car owners, we expect our cars to be in the best shape possible. Even if the problem occurs only once in a while, it is still an annoyance, as it should be! After all, we have paid a lot of money for our ride, and it simply doesn't have enough miles (or age) on it to already be giving us trouble!

In this business, intermittent problems are a technician's worst nightmare. Everything the technician knows about the complex systems on a vehicle cannot be put to good use until the technician can see the problem for himself. Sometimes, getting that little noise or vibration to reoccur can be a particularly grueling task. For example, I have had many cars that I have test-driven for miles and miles, and I still could not hear the noise the customer heard. It wasn't that I did not believe the problem existed; it was just that I could not “catch it red-handed”. Even with the most sophisticated test equipment, many times duplicating the customer's concern is crucial to an effective repair.

Automotive professionals have long been thought to have a “computer that can tell us what is wrong with the car”. Does such a tool exist? The truth is that there is not a simple answer to this question. We do have computers (called scan tools), and we can hook them up to the car, but they do not directly tell us what is wrong with the car. An automotive technician has to rely on his education and experience to look at the information this tool gives him. Only then can he diagnose what is wrong with the vehicle.

There are many times the scan-tool helps tremendously with the repair. There are other times when it tells us absolutely nothing! It just depends on what that problem is and more often than not, whether the technician actually experiences the symptoms for himself.

To give you some idea of what this tool does, imagine that your neighbors have a noise in their house that they can't quite locate. It occurs only once in a while, but not often enough or regularly enough to find. They know that you are a house noise specialist. Even being the specialist that you are, can you even begin to imagine all the possible causes of that noise? Perhaps it is a creaking door? Maybe wind noise or a rattling water pipe? Maybe there is an animal (though we hope not!) in the attic that is running around! The list could literally go on for miles.

Next, imagine yourself walking into their house, trying to find a noise that they heard, and trying to find it as quickly as possible so that you do not lose their future business. To make matters even worse, you can't seem to get the noise to reoccur while you are there, no matter what you try! What do you do next?

Easy-- you connect your “computer” to the house (a top-of-the-line “house scan-tool”). This tool doesn't tell you what the noise is exactly, but it does tell you that the noise last occurred in the living room at 11:51am when the house was at 67 degrees. (a little reminiscent of the game “Clue”?)

You see, this tool, though it did not tell you exactly what was wrong with the house, did narrow your search range. It would probably still be necessary for you, the home noise specialist, to hear the noise to determine its source. However, you now know that a good time to begin your quest would be around 11:51 in the morning with similar temperatures. You are no longer blindly looking for this noise, but have some clue as to when and where to start.

It is similar with an automotive scan-tool. The tool breaks our search down into a manageable area, and we can use these clues to guide us to our answers, but the answers are not given to us. Maybe one day in the future, they will be. For now, though, we will keep on using our equipment to keep the vehicles in the Roanoke Valley in top-notch condition.

The next time you have to take your car to the shop, remember to have patience with your trusted Automotive Technician. I am sure that he wants to get your car back to you as quickly as possible, but he also wants to be sure that the problem has been corrected. After all, every shop loves to see their customers coming back, but want to make sure they don't have to come back for the same problem.
 

Hunter Taylor is the automotive department head at Halifax Community College. If you have any questions about this article or other aspects of automotive technology, please contact Hunter at taylorh@halifaxcc.edu.