Jeff Taylor boasts a 34-year career in the automotive industry with Eccles Auto Service in Dundas, Ontario, as a fully licensed professional lead technician. While continuing to be “on the bench” every day, Jeff is also heavily involved in government focus groups, serves as an accomplished technical writer and has competed in international diagnostic competitions as well as providing his expertise as an automotive technical instructor for a major aftermarket parts retailer.
Keeping the internal combustion engine as close to the stoichiometric ratio as possible will result in optimum catalytic converter efficiency and fuel economy. The stoichiometric ratio simply means that all the air (14.7 parts) and fuel (1 part) going into the cylinders are being converted to water and carbon dioxide exiting the exhaust. This is the perfect combustion reaction, but this desired stoichiometric operation can’t happen without fuel control.
The process of supplying air to the internal combustion engine’s cylinders is called aspiration, and it involves the induction or intake system of the engine. Engine aspiration takes two forms: naturally aspirated (NA) or forced induction.
Unless you have just started in the automotive field in the last few weeks, you likely have faced this work order. A customer is concerned about exhaust noise. You get in the vehicle and start the road test. The exhaust is quiet, but the familiar hum or growl of a wheel bearing is oh so familiar.
Performing diagnostics is something many of us do each day, without much thought, but most seasoned technicians have a detailed diagnostic approach that they employ. They have an action plan — a diagnostic checklist — that they follow from start to finish with remarkable success.
While the installation of the correct engine oil may not be an important item to a customer when they arrive at our shop for service, the type of oil that is installed in the engine is beyond important. As technicians it is our job to ensure that the correct engine oil is installed that will meet or exceed what the manufacturer expects.
The spark plug has a straightforward job to do. It’s responsible for igniting the air/fuel mixture in the engine’s combustion chamber initiating the power stroke. But this task is far from simple. The spark plug’s operating environment is extreme with combustion temperatures reaching 1500 F and peak cylinder pressure reaching 1,000 psi or more.
Electronic Power Steering (EPS) is now standard equipment on virtually all new models of vehicles sold. One reason is clear: it removes the parasitic drag of the constantly turning, belt-driven hydraulic pump used to supply the hydraulic force to move the steering mechanism.
More original equipment manufacturers are incorporating automatic high beam systems as a safety feature in vehicles. So how does this technology work and what can we expect to see as these vehicles start showing up in our shops for service?
For an engine to run most efficiently and supply the catalytic converter with the proper gasses, it can convert to non-harmful emissions, the engine’s air-fuel ratio must run as close to the proper stoichiometric ratio as possible.
Many technicians start to feel uncomfortable about a diagnostic situation if the scanner only shows U-codes, but if the scanner powers up but will not communicate, that uncomfortable feeling intensifies.
Today’s modern ignition system normally will use a single ignition coil per cylinder, mounted directly or very close to the spark plug: the Coil On Plug (COP) design. Some systems use an individual coil and a small ignition wire in a Coil Near Plug (CNP) setup because the location of the spark plug in the cylinder head won’t allow enough room to directly mount a coil on the spark plug, I consider this a version of COP.
Automotive technicians all have their own individual style and approach to diagnostics and education. But most techs will tell you that if they understand how the system is supposed to work and the components involved, the diagnostic repair journey is usually easier. Automotive technology is constantly changing, it never seems to stop, but keeping up with this constant change is a demanding task.
Diagnostics can seem tricky and daunting at times. Just the sight of a “U” based code can be intimidating to even the best diagnostic technicians, but if a U0028:00 MOST bus code is set and you are dealing with the complaint of no center stack or no radio operation on a GM car or truck, where do you even start and what the heck is the MOST bus?