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Tech Tip: Engine Analyzers Combine the Capabilities of Many Diagnostic Tools into One

When most people think of an engine analyzer, they think of a big box console with automated test capabilities that can detect a wide variety of faults. There are still some machines like these today, but many of the features of a traditional engine analyzer are now available in top-of-the-line scan tools.

AC Update: Running A/C Diagnostic Tests Before Dash Surgery

I must have worked on Mercedes-Benz automobiles for 15 years before I ever replaced an evaporator. Through the 1970s, we pulled many an evaporator out of 107 and 116 chassis models to repair a poorly designed interior drainage system. The early models had little flappers on two interior tubes that carried the condensation to a

Mazda Tech Tip: Hesitation/Surge or MIL on with DTSC P0102/P0103

The Malfunction Indicator Lamp (MIL) may illuminate with diagnostic trouble codes (DTCs) P0102 and/or P0103 on any 1998-’99 Mazda B-Series 2.5L.

Diagnostic Dilemmas: Diagnosing Rodent Damage

Of all the technical innovations of the past century, the plastic-insulated copper wire is one of the most dependable components found in the modern automobile. Sure, this summer I had three different cases of the copper wire actually being broken inside the plastic insulation. In the first two instances, I had the intake air temperature

TechTalk: A Chevy Tahoe with Shifting Issues

A customer with a 1996 Chevy Tahoe brought the vehicle in, stating that it was shifting erratically, the cruise control would surge from 50 mph to 60 mph and then cut out completely and the speedometer, at times, was drifting. (This Tahoe had a 5.7L vin R engine with a 4L60E transmission coupled to a

VW OBD II Revisited: Good Vehicle Service History Helps Determine Causes of Repeat Failures

After 10-plus years of dealing with OBD II, it should be apparent that we are on a learning curve that probably has no end. Almost daily we have a VAG model come into the shop with a check engine light on, or a “state OBD II failure” form. Although we have the latest scanner software

Diagnostic Solutions: Identifying Ignition Switch Failure Symptoms

Although the basic ignition switch has remained unchanged for many years, the way it supplies electrical current to modern on-board electronics has made it a key factor when diagnosing intermittent failures in various electronic operating systems. Going back into automotive history, the ignition switch’s sole purpose on early imports was to energize the primary ignition

Servicing Ford 4-Cylinders: Contour, Escort, EXP, Focus, Probe, Ranger & Tempo

Ford has used a variety of four cylinder engines over the years, ranging in displacement from 1.6 to 2.5 liters (see engine application chart on page 22). All of these engines are overhead cam engines, some with a single cam others with dual cams, and all have timing belts that need to be replaced at

Performance Upgrades: Tuning, Tweaking & Boosting Your Way to New Profits

The import performance market offers a unique service opportunity for you. Import vehicle owners are accessorizing their vehicles like never before, and many are buying aftermarket performance parts in record numbers. Though many of these parts are sold to people who can install the parts themselves (things like wings, spoilers, lights, big bore mufflers, etc.),

Tech Tip: Air Flow Sensors – Understanding Their Function and 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.