Diagnostic Dilemmas: Getting In-Sync with a Couple Wranglers
It’s axiomatic in the diagnostic trade that, as soon as one thinks he has command of a particular system, the gods of technology pitch a curve ball that unerringly slips under the swing of the diagnostic bat. Not that I’ve never seen a 4.0L Jeep engine before; I’ve serviced dozens, perhaps hundreds of them. The
Diagnostic Solutions: A Little Homework Goes a Long Way….
In Diagnosing Intermittent or Hard Starter Failures
Under Pressure:TPMS Diagnostics
Have you ever noticed the sides of at least one tire excessively bulging on the car ahead of you in traffic? Of course you have. You’ve likely also found a high number of improperly inflated tires on vehicles that roll into your shop on a regular basis. Improperly inflated tires are commonplace. The National Highway
Diagnostic Oddities
This article is dedicated to some Ford specific issues that, after being brought to light, can save your shop thousands of dollars in wasted time and liability. There may be some other makes out there with some similar designs and quirks, but the only technical references will be for Ford vehicles. By Glen Beanard Giddy
Engine Diagnostics: Mazda
We’re going to take a look at the Mazda line of cars and trucks with an eye on driveability service and diagnosis. In particular, we’ll look at some driveability problems that may result in an illuminated check engine light, as well as some problems that will illuminate the light but may not result in a
Troubleshooting MIL Issues: OBD II & “CAN” Scan Tool Diagnostics
The Malfunction Indicator Lamp (MIL) is one of the most misunderstood warning lights on vehicles today. Most motorists have no idea what the light means or why it’s on. Some think the MIL light is an oil change reminder light. Others realize something must be amiss to cause the light to come on, but don’t
Diagnostic Dilemmas: The Misfire Code As a Symptom
Without question, the 1996 and newer OBD II systems have greatly simplified the diagnostic process. Veteran mechanics well remember the technical loopholes that riddled the old proprietary OBD I systems. All too often, the complex diagnostic charts supplied by the auto manufacturers were time-consuming, erroneous and often concluded with the infamous “replace with component of
Diagnostic Solutions: Oxygen Sensor Diagnostics
Once considered leading-edge technology, today’s oxygen sensor has become a commonplace service item on modern vehicles. Popularly introduced in the 1970s, the Lambda or, as it’s more popularly known, the oxygen sensor, rapidly became standard equipment as it’s a vital component of closed-loop or feedback fuel control technology. By using a voltage input from the
Diagnostic Dilemmas: The Pressures of Intake Manifold Vacuum Tests
Several years ago, a retired school teacher brought in a 1994 Chevrolet S-10 Blazer that had developed an intermittent rough idle condition. Although a rebuilt engine had been installed a year before, and all of the wiring and vacuum hoses looked as if they were in factory condition, I took nothing for granted. An ignition
Diagnostic Solutions: Throttle Position Sensors
Although conventional throttle position sensors attached to the throttle shaft are considered basic technology on modern engine management systems, the conventional throttle sensor plays an important role in its relationship with other sensors. The voltage inputs of most throttle position (TP) sensors may, for example, be coordinated with the barometric pressure (BARO), manifold absolute pressure
Fundamentals of Electrical System Diagnosis
Electrical principles, like voltage, amperage and resistance, can be described as cars passing along the roadway. Voltage would be the vehicle’s speed, amperage would be the number of vehicles on the road at the same time, and resistance would be the potholes in the road’s surface. Basically, electricity is a supply of atoms with an
Servicing Maintenance-Friendly VW Engines
Volkswagens have always been maintenance friendly. From the very first models, ease of repair and durability have been built into the design. VW has managed to keep basic maintenance procedures relatively uncomplicated throughout the years. In this article, I’ll cover some of the more common underhood procedures on common VW models and include some tips