Can I remove the stock PCM?
Yes, you can! This type of installation is usually called a “full installation” or “full stand-alone installation.” In order to complete a full installation, you must order MegaSquirt ECU with the hardware to drive a tachometer, control the radiator fan relays, and fuel pump and auto-shutdown (ASD) relays (if any). For certain applications, such as the 420A/Neon, you must also install an external alternator voltage regulator.
To drive the tachometer, simply be sure your MegaSquirt ECU is built with a tachometer output circuit. MegaSquirt ECU’s in SymTech Labs’ Complete MegaSquirt EMS Kits include this optional circuit. Otherwise it can be purchase through our MegaSquirt Option Service.
For radiator fan relay control, be sure your MegaSquirt ECU is built with a programmable general purpose output (GPO) circuit. MegaSquirt ECU’s in SymTech Labs’ Complete MegaSquirt EMS Kits include this optional circuit. Otherwise it can be purchase through our MegaSquirt Option Service.
For both fuel pump and ASD relay control, you must configure the standard fuel pump relay driver to handle two relays instead of just one. See this article for more information.
Alternator voltage regulators are included in SymTech Labs’ Complete 420A/Neon MegaSquirt EMS Kit.
