Over the past 20 years, we have seen water pumps and cooling systems evolve to improve start-up emissions. We have also seen a revolution in the material used for engine blocks, cylinder heads and cooling system components. Today, coolant may flow through an iron block, aluminum cylinder head and plastic thermostat housing.
Chances are your foot will know the condition of a vehicle’s brakes and the quality of the brake pads before your mind puts it all together. Consider this: Stopping a 4,000-lb. vehicle requires a driver to press on a pedal to generate friction at the wheels. What happens in between the pedal and pads can determine how much pressure the driver is required to apply to stop the vehicle in a safe distance.
The customer will not be happy if he brought the car in for a knocking noise, was sold a couple hundred dollars worth of struts and/or ball joints, etc., and the noise is still there. If he then takes the car elsewhere and the knocking noise is fixed with a couple of $20 sway bar bushings, that guy is going to think he got beat. This underscores the importance of addressing the customer’s complaint before that vehicle leaves your shop.
Leave your wrenches in your toolbox because in this month’s Diagnostic Solutions, we’re going to explore how to diagnose many common powertrain control module (PCM)-related driveability and electrical problems by following what I call The Electronic Trail.