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Who’s at Fault?…Top 10 Domestic Diagnostic Codes & Fixes

A Check Engine Light that’s illuminated is always a sign that something is wrong. But what? You usually can’t tell until you plug in a code reader or scan tool and read out the code(s) that have turned on the light. At least then you have a starting point for further diagnosis. Some people think

Tech Feature: Getting Up to Speed on Hybrid Vehicles

Hybrids are hot. As the price of gasoline goes up, so does the demand for new vehicles that can squeeze more miles per gallon from every drop of gasoline. Hybrids do that by combining the best of both worlds: electric power for low-speed, stop-and-go driving, and gasoline power for highway cruising and long-range driving.

Hybrids: Basic Service & Safety Procedures

Hybrids are hot. As the price of gasoline goes up, so does the demand for new vehicles that can squeeze more miles per gallon from every drop of gasoline. Hybrids do that by combining the best of both worlds: electric power for low-speed, stop-and-go driving, and gasoline power for highway cruising and long-range driving. Current

Diagnostic Dilemmas: Symptom Diagnosis…The Journey Begins

When I first began my automotive career way back in 1957, the symptoms of an ailing engine were very apparent. A carburetor with a worn accelerator pump, for example, would characteristically stumble on acceleration and a closed-up set of distributor contact points would cause the engine to become very sluggish. Low fuel pressure caused by

Diagnostic Dilemmas

It’s Mechanical, Stupid! Just about every student of politics remembers President Bill Clinton’s famous campaign slogan, “It’s the economy, stupid!” Allow me to paraphrase by saying, “It’s mechanical, stupid!” Yes, that’s right, mechanical failures can cause diagnostic trouble codes and, all too often, we tread the Primrose Path because we become lost in a maze

Engine Performance

Smart Diagnostics Begin With Basic Checks and Solid Service Information

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

Making Sense out of Sensors

Sure, you may be familiar with some basic sensor operation. But as an automotive technician, you may not really understand all of the ins and outs of many common sensors. Do you really understand how they work, how the PCM views them and the possible scan tool and DVOM results when things go wrong? If

Tech Tip: Oxygen Sensors – Monitoring Converter Efficiency

In 1996, automakers did the aftermarket a huge favor. They added "downstream" oxygen (O2) sensors to their vehicles. The downstream O2 sensors are located just behind the catalytic converter, or on some Fords, in the converter itself.