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Joel, Auto technician
Category: Chevy
Satisfied Customers: 1603
Experience:  GM, ASE Certified Technician. Chevy, Buick, Pontiac, Olds. Over 18 Years experience and growing.
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What is the difference between a 5.3l MFI engine vs. a 5.

Resolved Question:

What is the difference between a 5.3l MFI engine vs. a 5.3l SFI engine?
Submitted: 7 years ago.
Category: Chevy
Expert:  Joel replied 7 years ago.

Hello and welcome.

The difference between the two is that MPFI uses what's called batch fire. Basically, the system fires all the injectors for one bank of the engine at once. .

SFI fires the injectors individually, so they're only firing the injector at the cylinder that needs fuel at a given moment.

SFI is more precise for better power and mileage.


Customer: replied 7 years ago.
Is the 5.3L SFI a reliable engine? Can modifications be made (i.e. installing a chip, C.A. Intake) to improve mileage, etc?
Expert:  Joel replied 7 years ago.

Yes, the 5.3 is a very good engine.

There are many aftermarket mods that can be done.

K and N air filters and air intake kits, colds air intake kits,

computer chips, etc. Here is a link to one such system...

Joel and other Chevy Specialists are ready to help you