TDI Driveability: Carbon Plugging of the Intake System
Volkwagen has been selling diesel-powered cars in the U.S. for almost 30 years. Turbocharged versions have been available for 25. That is a lot of experience and a testament to the development of a reliable, efficient and durable powerplant. The introduction and development of the TDI (turbocharged direct injection) brought the VW diesel into the
Tech Feature: Performance Modifications…Getting a ‘Handle’ on Your Customers’ Tuning Needs
The sport compact car market is hotter than ever. The market has moved beyond the simple bolt-ons such as wheels, tires, brake rotors and spoilers. It’s not unusual today to see sport compact engines producing upward of 400 horsepower on the street. With so much power under the hood, the challenge is getting the horsepower
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