For years now, enthusiasts have been retrofitting early project cars with LS-series engines and Gen III PCM conversions. The available features (cable or electronic throttle, cruise control, forced induction support, and so on) make the Gen III PCMs highly desirable for nearly any conversion. The following projects are fine examples of Gen III control systems […]

Modern fuel injection systems have many sensors and switches installed at key locations on the engine and transmission to allow the engine (and transmission) computer to operate in the ways they are  intended. These sensors and switches are used to deliver the proper amount of fuel, the correct amount of spark timing, the most appropriate […]

As the owner of EFI Connection, engine wire harness manufacturing is my specialty. In the early days of my career, I took on used harness rework for 1985–1992 Camaro and Firebird owners who wanted to add a TPI system to their car. I’ve also revised newer LS harnesses for customers who have relocated components in […]

All Gen III vehicles were available with cruise control. Engines with a cable-actuated throttle body require an electronic cruise control module with an internal stepper motor to pull and release a throttle cable to maintain vehicle speed. Engines with an electronic throttle body rely on the TAC module to increase and decrease throttle blade angle […]

All too often PCM-controlled (or monitored) air conditioning is overlooked after the engine has been swapped, the new wire harness has been installed, and custom calibrated PCM has been received from the tuner. The A/C system is commonly one of the many “I’ll think about that later…” tasks as the excitement builds for the first […]

Gen III PCM control goes beyond the engine to be one of best solutions for electronically controlled 4-speed automatic transmissions. Owners not using the LS1 PCM for engine control must look to the aftermarket for a standalone transmission controller that may cost in excess of $1,000. While many who desire an automatic transmission choose either […]

Gen III PCMs are powerful control modules but they are of little use without tuning software to change engine (and transmission) operating parameters. Before getting too far into a discussion of electric fans and PCM calibrations, it is important to first consider air conditioning control. This Tech Tip is From the Full Book, HOW TO USE […]

General Motors introduced electronic throttle, or drive-by-wire, with the LS1 engine in the 1997 Corvette. Electronic throttle was released before cable throttle for the LS-series engine family. In 1998, the Camaro and Firebird received a cable throttle LS1 engine. The GM trucks received LSseries engines in 1999 and, depending on make/model, were available with either […]

Let’s begin this chapter by agreeing that the “LS1 PCM” is just an ECU that has the designed purpose of controlling the sequencing of ignition and injector events based on a variety of sensor inputs. We can then agree that this ECU is uniquely programmed so that combustion results are favorable so that the stoichiometric […]

Production GM vehicles rely on the PCM to provide signal outputs to control the engine, gauges, electric fans, emissions equipment, air conditioning, and other equipment.s This Tech Tip is From the Full Book, HOW TO USE AND UPGRADE TO GM GEN III LS-SERIES POWERTRAIN CONTROL SYSTEMS. For a comprehensive guide on this entire subject you can […]