Fuel Pump Diagnostics
Electric fuel pumps are a vital part of any electronic fuel injection system because achieving an accurate air/fuel mixture ratio depends upon the fuel injector receiving adequate fuel pressure and volume. Because electric fuel pumps have moving parts that wear out, they also have a relatively predictable service life and, therefore, become a predictable profit
Diagnostic Dilemmas: Battery-Related Driveability Issues
Any experienced automotive trainer will tell you that the automotive starter battery is the foundation of a vehicle electronics system. Of course, most of us nod our heads in agreement and then proceed to diagnose a driveability problem without first testing the battery’s condition! Unfortunately, short-cut procedures don’t work on the really tough no-code engine
Shock Replacement Option Require a Proper Assessment of Customers’ “Ride” Expectations
Shock absorber replacements are unique because they represent a big ticket, high profit margin, low liability sales opportunity that happens at least once or perhaps twice during the normal service life of a typical vehicle. Modern shock absorber design is also becoming much more sophisticated than it was just one short decade ago. In conventional
Timing Belt Replacement: Safeguarding Your Customers’ Vehicles From Major Engine Damage
Although better materials and manufacturing technology have extended the timing belt replacement intervals on many nameplates, timing belt replacements remain one of the most profitable scheduled maintenance services. They continue to be profitable because many other scheduled services like spark plug replacements, filter replacements, coolant changes and transmission fluid changes can be packaged with a
Causes & Cures for Disc Brake Problems
There are as many causes as there are cures for disc brake problems. Brake pedal pulsation tops the list, while disc brake noise and brake pedal sensitivity follow as second and third place contenders. Most of these problems can be avoided if technicians have the right parts and follow the correct procedures. Let’s begin by
Ninety-Nine Times Out of a Hundred…
Let’s face it: all of us occasionally get that haunting feeling of inadequacy when a simple pattern failure turns into “rocket science.” Like most technicians, my rocket science feeling happens most often when the problem at hand doesn’t fit within the confines of my previous experience. Ninety-nine times out of 100, my experience works to
Component Connection: Water Pumps…Why They Fail and When to Replace Them
If you’ve wondered how much work a water pump must do, remember that only about 30% of the heat energy produced by combustion results in mechanical energy. That estimate, of course, is a mathematical comparison between the heat value of the gasoline going into the engine, and the heat value of the mechanical energy coming
Piston Technology: To Power Today’s V8s
The performance piston business today is hot thanks to a strong racing market and the introduction of new OEM engine families such as Chevy’s LS1/LS6 V8s, Ford’s 4.6/5.4L V8s and Chrysler’s Hemi. Piston manufacturers are introducing new performance pistons for all of these applications as well as refining existing piston designs to reduce weight, and
Diagnostic Solutions: Air Flow Sensors…Understanding Their Function & Potential Problems
Most of us remember the “good old days” when an engine’s air/fuel (a/f) ratio was controlled by a mechanically operated carburetor. Due to the inherent design limitations of mechanical systems, however, carburetors don’t respond efficiently to changes in barometric pressure, temperature and humidity. In the quest for improved fuel economy and reduced exhaust emissions, import
Ignition Control Modules
Their Important Role in Creating Voltage at the Spark Plug Electrode
Diagnostic Dilemmas: Code Talking
This being the 60th anniversary of the end World War II, I’ve seen several television programs and movies about how Navajo Indians used their native language to relay a simple military code in the war’s Pacific theater. In order to break any code, it’s important to understand the language in which it’s transmitted. The Navajo
Component Connection:Becoming a Better Belts & Hose Inspector
Accessory drive belts and coolant hose replacements are perhaps the most popular and lucrative add-on services in the independent repair shop. Because belt and hose inspections are included in auto manufacturers’ scheduled maintenance charts, service writers at most well-managed shops recommend a belt and hose inspection along with tuneup, oil change, starting, charging, cooling, air