Diagnostic Dilemmas: The Effects of Warm-Up Laps on a Running Engine
Most diagnostic technicians have experienced the frustrations of troubleshooting temperature-related engine performance problems. All too often, the true nature of the problem is concealed by the very fact that it occurs only at specific engine temperatures. If the engine quickly passes through the critical temperature range needed to duplicate the problem, the problem can easily
Friction Material Selection
Because today’s lighter and more friction-efficient disc brakes have become very sensitive to differences in friction materials, the issue of selecting a quality brake pad is becoming increasingly relevant to the quality-conscious installer. To illustrate, aftermarket manufacturers of high-performance disc brakes offer literally dozens of racing pads that are qualitatively equal, but vary widely in
Ball Joints & Bushings: Worn Components Take Their Toll on Advanced Suspension Technologies
Too often, shop owners and technicians alike assume that suspension systems haven’t changed much in the past 20 years. In reality, nothing could be farther from the truth because today’s import vehicle may incorporate a number of technologies that can be affected by worn steering and suspension components. To illustrate, we’re beginning to see electronic
Selling Service for Low-Maintenance Ignition Systems
ition system maintenance as long as it feels like it’s “running good.” In reality, spark plugs eventually develop high electrical resistance because the electrodes wear away. When this happens, the secondary ignition voltage will increase until the ignition coil, ignition cable, spark plug boot or spark plug develops a high-voltage leak. When a high-voltage leak
Selling Oxygen Sensors
As modern OBD II technology marches on, it’s clear that the zirconia-based oxygen sensor now is being sold more as a basic repair part than as a preventive maintenance part, and it changes the way we diagnose and sell oxygen sensors. To illustrate the difference, let’s remember that an oxygen sensor replacement used to be
Searching for the Diagnostic Path
Most recently, I’ve found myself dealing with an increasing number of random, multiple-code complaints that involve computer operating strategies and networking communications issues in which the multiple trouble codes or DTCs tend to be symptomatic, rather than indicative, of a component failure. A basic illustration of what I’m talking about is a simple DTC 44,
The Lube, Oil and Filter Market
As with everything else under the automotive sun, technology is changing the lube, oil and filter market. To be more specific, modern technology is making it possible to use the vehicle’s on-board engine management system to mathematically determine the length of an oil change interval. At the most basic level, the PCM simply adds up
Diagnostic Dilemmas: Playing the Diagnostic Shell Game
More often than not, deciphering diagnostic trouble codes is like playing a high-tech version of the old circus sideshow “shell” game. In the trouble code shell game, we are led to believe that the pea (diagnostic solution) is hidden under one of the shells (DTCs) stored in the diagnostic memory. Unfortunately for the diagnostic technician,
The Fuel Injector Market and System Configurations
Looking back into automotive history, it’s hard to believe that carburetors were still being installed on import vehicles as late as 1989! But carburetors require all sorts of external vacuum and electronic gimmickry to control the cold-starting, fast idle, hot idle and low-speed cruise functions. Electronic fuel injection has since replaced carburetors in all import
Confronting the Complete Cooling System Service
By now, it’s obvious to most service shops that cooling system service is an absolute “must-do” on any nameplate. Once a cooling system suffers long-term neglect, it turns into an ongoing source of problems for the owner and his service technician because, when corrosion starts to take place, the effects can’t be reversed. For that
Thermostat Technology
Although the humble thermostat isn’t generally considered to be a “high-tech” component, it continues to serve a number of very critical functions in the modern, computer-controlled import vehicle. To better understand these functions, let’s first consider that carbon and water are two major by-products of internal combustion that accumulate in an engine’s motor oil. Unfortunately,
Radiator Diagnostics & Troubleshooting
Although radiators aren’t glamorous, high-tech replacement parts like wide-band oxygen sensors and Karman-Vortex air flow sensors, diagnosing and replacing them when they become defective is becoming a more important part of vehicle maintenance today. There are at least three reasons why radiators are becoming important maintenance items. First, late-model vehicles are now being driven well