How To Use The Engine Performance Section

NOTE: This article is generic in nature and all information does not apply to all vehicles. For vehicle specific information, see the appropriate articles in the ENGINE PERFORMANCE category.

Congratulations, you have purchased the most advanced automotive repair and service information available. This information can help you, as a professional automotive technician, to maintain top vehicle performance, and correct driveability problems on today's high-tech vehicles.

For your convenience and ease in use, all of our engine performance service and repair information is consistently organized by manufacturer, using a progressive diagnostic/workflow approach. Due to the differences in how each manufacturer approaches diagnosis and repair, once started and inside of an article, that manufacturer may drive the workflow in a direction other than what is outlined here.

The progressive diagnostic/workflow of our data is as follows:

APPLICATION to identify vehicle and system usage.
EMISSION APPLICATION to identify emission system usage.
SPECIFICATIONS to quickly find an engine performance service specification.
ADJUSTMENTS to perform engine performance related routine adjustments.
THEORY & OPERATION to familiarize yourself with new systems and technologies.
BASIC DIAGNOSTIC PROCEDURES located under TESTING & DIAGNOSTICS, also referred to as BASIC TESTING, is used for performing a basic vehicle inspection and is also the starting point for diagnosis of a "no-start" condition.
SELF-DIAGNOSTICS located under TESTING & DIAGNOSTICS, also referred to as TESTS W/CODES, is where manufacturer specific procedures for retrieving, identifying and diagnosing DTCs (trouble codes) retained in a control modules memory are located.
TROUBLE SHOOTING - NO CODES located under TESTING & DIAGNOSTICS, also referred to as TESTS W/O CODES, is where an engine performance problem that does not set a DTC can be potentially isolated through either a SYMPTOM or INTERMITTENTS duplication procedure.
SYSTEM & COMPONENT TESTING located under TESTING & DIAGNOSTICS, also referred to as SYSTEM/COMPONENT TESTS, once directed to this article, specific system and component tests can be performed to help isolate faulty component/system prior to replacement.
PIN VOLTAGE CHARTS provide supplemental information to help determine correct control module input and output signals. Pin charts may also be referred to as PID charts by some manufacturers.
SENSOR RANGE CHARTS help determine if a sensor is out of calibration. In some cases an out-of-calibration sensor will not set a DTC (trouble code), resulting in difficult to diagnose driveability symptoms.
VACUUM DIAGRAMS help determine correct routing of vacuum hoses when reinstalling components or performing emission inspections.
REMOVE, OVERHAUL & INSTALL provides procedures necessary for removing and installing engine performance related components.
WIRING DIAGRAMS can be used to identify circuits, terminals, wire colors and components referenced in testing procedures. NEW COLOR WIRING DIAGRAMS (system diagrams) provide an easy method of identifying and tracing circuits.