Diagnosing a driveability problem starts with the customer interview. When you are able to obtain the proper details about the vehicle's symptoms, you will be able to diagnose the source of the problem more efficiently. Clues provided by the customer, such as "vehicle starts but runs rough until warm; worse when wet," is invaluable information to get you started on your diagnostic routine and lead you to a successful repair.

After pulling in the car, open the hood, mist the secondary system with water or your preferred solution and, nine times out of 10, the problem becomes obvious and you know that it will be a successful repair. Such a scenario produces a good profit on the parts, it's a nice labor job and the perfect opportunity to check the customer's vehicle for related, necessary services and parts (such as spark plugs, filters and fluid changes).

Let's take a look at some of the problems you are likely to see when faced with diagnosing a driveability complaint on a Hyundai. Like any other vehicle, most driveability problems will be traced to basic systems. Even if you're armed with good information, it's important to road-test the car and duplicate the complaint before attempting any repairs. This is also the time to make note of any other problems you may have noticed that the customer failed to mention. Don't overlook the little items, such as lubricating a squeaky door or tightening the armrest. Cust...