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Chevrolet 3.4 Intake Manifold Gasket

The 3.1 and 3.4 GM intake gaskets are a high failure item. Use this article as a guide before starting the job to save time and avoid mistakes.

Ford 4.6L Intake Manifold Replacement

This article will guide you through an intake manifold repair on the 4.6 liter Ford engines found in many Mustangs and full-size sedans.

GM 4.3L Intake Manifold Repair

This article will guide you through an intake gasket repair on the 4.3 liter GM engine found in many Chevrolet trucks.

GM 5.7L Intake Manifold Repair

This article will guide you through an intake gasket repair on the 5.7 liter GM engine found in many Chevrolet trucks.

Volkswagon Passat Water Pump

Before tackling a water pump or timing belt on a 2.8 liter V6 Passat, you will want to read this article. If doing work on a 1.8 liter 4 cylinder Passat, the first part of this article will still come in very handy with step by step instructions for removing the front end including bumper, radiator and core support.


Basic Electrical System Testing

This article is still under construction, check back periodically for more updates. Please direct all comments and suggestions to the feedback page, we would like to know which other basic tests you would like to see covered.


Not sure if the repairs have reduced emissions enough to pass the IM240 test? Check out Scott Shotton's method of repair verification.

Introduction to Mode$06 Data

Mode$06 data can be very handy in many diagnostic situations. Learn the basics with this article and be sure to check out the Mode$06 section for manufacturer specific Mode$06 details and conversion calculators.

Scope Basics

Learn the basics, or brush up on the use of your digital storage oscilloscope(DSO).This article covers some basic understanding and best practices for using your DSO properly.



Cam and Crank Sensors

There are several different types of cam and crank sensors. Learn what each type is and how to properly test them.

Chrysler Evap Testing

This article shows how to seal a Chrysler Evap system even without the use of a scan tool. Once sealed, an evap approved smoke tester can be used to pinpoint an evaporative emissions leak.

Coil on Plug Ignition Testing with a Scope

Are you trying to locate a misfiring coil on a COP ignition system? This article shows what to look for when viewing primary ignition patterns on a scope.

COP Diagnostics Part II

Learn to use a low amp probe to identify misfiring coils and coils that may soon fail but are not yet causing a misfire.

Ford Mode$06 Misfire Data

Since Ford vehicles do not offer cylinder specific misfire information in the regular scan data, Mode$06 information is very useful with Ford vehicles. Learn how to locate which cylinder is misfiring in seconds by using Mode$06 information.

Fuel pumps and low amp probes

The low am probe and oscilloscope are invaluable when diagnosing intermittent fuel pump failures. Lean the techniques used by top techs to locate a faulty fuel pump even if the pump appears to be working fine at the time of testing.

Ignition Coil Current Ramping

Ignition coil current ramping is very useful in diagnosing ignition system faults. Learning to use the low amp probe and scope for diagnosis will be a huge time saver and increase diagnostic accuracy.

Mass Air Flow Meter Testing

Learn to perform the snap throttle test to help in diagnosing faulty mass air flow sensors. Also, be sure to check out the online MAF analyzer in the tools section of

Oxygen Sensor Testing

Oxygen sensors are one of the most critical sensors on a vehicle. Learn proper methods for finding sluggish sensors.

Secondary KV isn't Everything

When using an ignition scope to diagnose a misfire, be sure to look at more than just the firing kv of each cylinder. Just like the title says, secondary kv isn't everything. There is much more to an ignition pattern than just kv

Volkswagen/Audi Scan Tool Diagnostics

Scott Shotton shows you how to tackle Volkswagen scan tool diagnostics. Also learn to perform throttle and kick-down adaptions.


Alternator Altercation

A great article covering some basics of electricity and alternator diagnosis.

Debunking the battery

All you ever wanted to know about batteries and more.

Ford EGR systems

This article covers the theory and operation of Ford EGR systems including the newer ESM style EGR system.

Ford Escape Hybrid

Another great article by Glen Beanard on Ford's mini-SUV Hybrid.

Ford ETC (Drive by wire)

Electronic throttle control systems are becoming commonplace on many of today's vehicles. This article covers the theory and operation of Ford's drive by wire systems.

Ford Flex Fuel Systems

Learn how Ford flex fuel systems work and how to properly diagnose problems and drivability concerns with flex fuel vehicles

Ford PATS Systems

Need to brush up on of Fords Passive Anti-Theft System? This article describes the functions of the various components and can help with PATS scan tool diagnosis.

Getting Started

Great article on electricity and how it relates to starters.

GM PassKey and PassKeyII Theft Deterrent

This article will give you a basic understanding of GM Passkey and Passkey II theft deterrent systems. The systems are easily diagnosed when you know what to look for.

Returnless Fuel System

Read about Ford's returnless fuel systems. Learn what to look for and how to test various components when diagnosing faults with these vehicles.