Fuel injectors vs mpg
Thread Starter
Intermediate
Joined: Nov 2000
Posts: 35
Likes: 0
From: PJS, N.Y.
Fuel injectors vs mpg
Since I have replaced my fuel injectors my gas mileage has been real variable, Anywhere from 16-22 mpg. With old injectors (only 3 were really working) mpg were pretty consistant around 22. Is this normal?
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
My mileage varies considerably. Steady speed on a flat interstate brings 30-32mpg; around town mileage will vary between high teens to low-mid 20s, depending on how agressively I drive.
I wouldn't worry about your varying mileage unless you notice that highway mileage is way low.
I wouldn't worry about your varying mileage unless you notice that highway mileage is way low.
Advanced
Joined: Dec 2001
Posts: 51
Likes: 0
From: Nashville TN
I've not really heard of MPG jumping around just from changing injectors.
First thing, are your driving habits varying significantly? Did you go back with stock replacement injectors or are they a different size/brand?
First thing, are your driving habits varying significantly? Did you go back with stock replacement injectors or are they a different size/brand?
Safety Car
Joined: Dec 2002
Posts: 3,655
Likes: 24
From: Charleston SC
as long as the injector constant is correct and the tune is right you should be able to use a wide and I mean wide range of injectors. keep in mind that just because an injector is a 32# injector that does not mean you can just change the constant to 32# and be done with it, it needs to be tuned untill you get the proper A/F mixture. I have 36#rs in my combo and I am getting 17 MPG in city trafic, to and from work, with my 383 and about 25MPG Hwy. The only time I see a variation is if my foot gets a little heavy.
Team Owner
Joined: Sep 2001
Posts: 62,146
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From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Assuming the tune is right and the injectors are working fine and arent bigger than 24, then you may have an O2 sensor failure.
