GM’s Vortec engines come with a Sequential Port Injection System (SCPI). Standard's Multi-Port Fuel Injection (MFI) System has several advantages over the original Sequential Central Port Injection (SCPI) system, including port fuel delivery and high reliability, better hot starts and reduced vapor emissions, and faster prime on hot restarts.
Improved hot fuel handling over SCPI system
Lack of poppet valve eliminates problem of deposit build-up
Improved spray injector nozzle design with longer seat and no valve ball reduces deposit buildup that can cause clogs
Enhanced pressure control at low recirculation rates
The above Multi-Port Fuel Injector is also available for the GM V8.
Tech Tip: For successful installation, lubricate injector tips and O-ring seals with transmission assembly gel, petroleum jelly or even clean engine oil. Do not use silicone.
Replacing the multi-port fuel injection (MFI) system on a GM V6 4.3L engine is a complicated job.
Our ASE-certified master technician shows you how it's done: