Operation CHARM: Car repair manuals for everyone.

Engine Control Module: Description and Operation: Overview

OVERVIEW
The Powertrain Control Module (PCM) features a multi-processor environment (one 16 bit microcomputer, two 8 bit micro-computers) allowing parallel processing of time critical operations. Dedication of one 8 bit processor (K4) to spark control and the other 8 bit processor (D3) to fuel control allows increases in throughput and reduced software complexity in the 16 bit microcomputer (Z2). The result is increased capability in the Z2 to handle overall strategy implementation, OBDII, and other computation-intensive processes. This approach allows control of up to a ten cylinder engine running in excess of 6,500 RPM.