At the shop vehicles come in broken and generally go out fixed. It is the in between part that can go astray sometimes.
The first part of any problem diagnostic process is to verify the customer’s complaint. Many times this is easier said than done. This is especially true when the vehicle is dropped off and the customer’s complaint should be obvious or it seemed that way when we spoke on the phone with the customer.
Mechanics are usually fussier than a lot of drivers are. We have spent a great deal of our lives at the wheel of all types of vehicles in various states of disrepair. We know when something is seriously or obviously wrong with your vehicle.
What happens when the customer’s problem does not present itself as we assumed? One man’s powerless car is another man’s powerhouse. One man’s gas guzzler is another man’s fuel sipper. One man’s Cadillac ride is another’s ‘worse than a one ton pickup’. The list can go on.
When a vehicle comes in with a driveability complaint: running rough, losing power, stalling, or simply won’t start, the next step is a road test. If all goes well the road test will reveal the problem immediately and the mechanic will be on his way to a solution.
That solution may not be as simple as the vehicle owner expects. “The car is losing power. It feels like it is not getting fuel. Needs a fuel pump.” Nope, not that simple! A fuel pump can be a XXXX dollar repair. No guessing allowed. That car has three fuel pumps. Which one is it?
Once the customer’s complaint has been verified (power loss) the mechanic will formulate a diagnostic procedure to find the culprit, be it a bad electrical connection, a plugged fuel filter, a bad fuel pump, or maybe an empty gas tank. The possibilities are many. The answer should be forthcoming though.
The other scenario, “No problem found” is another kettle of fish. Road test after road test, the thing runs great. What are we missing?
As mechanics we know cars. Fords have these problems. Chevs have those problems. VW always do this. When a problem presents itself we will diagnose from the most likely point of view.
Knowing the vehicle and it’s idiosyncrasies is not enough. We need to know the driver. How does the driver drive? Third gear at six thousand revolutions per minute up the hill to Rossland or fifth gear at twelve hundred revs? Huge difference.
One road test method will verify the complaint many others methods won’t. Knowing the man is as important as knowing the machine.