Injector Size vs. DIC MPG Readout
Thread Starter
Racer
Joined: Jan 2013
Posts: 354
Likes: 3
From: Athens TX
Injector Size vs. DIC MPG Readout
Hey guys,
LG just got done doing some work to my car and I have a question (since they're not open on the weekend). I had a bunch of work done, but I have a question specifically about the injector size in relation to the MPG readout on the DIC. I went from the stock injectors to 42 lb/hr injectors and I was watching my MPG on the way home and it showed I was getting great cruising MPG, but it seemed like I was actually using gas faster according to the gauge (could've been my imagination though). Now obviously I don't drive the car for MPG, but I would like to know if that reading is accurate or not. I know even stock it's not perfectly accurate, but is it possible that this reading is off a large percentage because of the injector change? If so, is there a way to change something in the computer so that it can read more accurately?
Thanks guys
LG just got done doing some work to my car and I have a question (since they're not open on the weekend). I had a bunch of work done, but I have a question specifically about the injector size in relation to the MPG readout on the DIC. I went from the stock injectors to 42 lb/hr injectors and I was watching my MPG on the way home and it showed I was getting great cruising MPG, but it seemed like I was actually using gas faster according to the gauge (could've been my imagination though). Now obviously I don't drive the car for MPG, but I would like to know if that reading is accurate or not. I know even stock it's not perfectly accurate, but is it possible that this reading is off a large percentage because of the injector change? If so, is there a way to change something in the computer so that it can read more accurately?
Thanks guys
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my point was that the dic avg mpg is not an accurate way to calculate your mileage hence why you're confused about why your gas gauge is going down fast but it says you get great mpg on the dic... I think it is more related to the tune and other mods like a cam that demand more fuel rather than the injector size... as far as changing anything in the pcm to correct it I have no idea
Thread Starter
Racer
Joined: Jan 2013
Posts: 354
Likes: 3
From: Athens TX
my point was that the dic avg mpg is not an accurate way to calculate your mileage hence why you're confused about why your gas gauge is going down fast but it says you get great mpg on the dic... I think it is more related to the tune and other mods like a cam that demand more fuel rather than the injector size... as far as changing anything in the pcm to correct it I have no idea
Pro
Joined: Jul 2011
Posts: 608
Likes: 17
From: South Lyon, MI
Changing the injectors should not effect the DIC reading IF your injector duty cycle is set properly. Your mpg (DIC) reading will depend on your injector duty cycle and how much fuel is being commended. Its hard to tell from your statement since all you say is injectors were changed..what else do you have done to it? Power? A/f ratios at wot, part load and steady state? All these things effect your dic reading and mpg.
Burning Brakes
Joined: Jul 2006
Posts: 763
Likes: 45
From: Long Grove IL
Changing the injectors should not effect the DIC reading IF your injector duty cycle is set properly. Your mpg (DIC) reading will depend on your injector duty cycle and how much fuel is being commended. Its hard to tell from your statement since all you say is injectors were changed..what else do you have done to it? Power? A/f ratios at wot, part load and steady state? All these things effect your dic reading and mpg.
A while back I did a quick fix for running lean on mine and just changed the injector size smaller in the tune, this made the MPG skyrocket. It claimed around 32 MPG around town.
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Thread Starter
Racer
Joined: Jan 2013
Posts: 354
Likes: 3
From: Athens TX
Changing the injectors should not effect the DIC reading IF your injector duty cycle is set properly. Your mpg (DIC) reading will depend on your injector duty cycle and how much fuel is being commended. Its hard to tell from your statement since all you say is injectors were changed..what else do you have done to it? Power? A/f ratios at wot, part load and steady state? All these things effect your dic reading and mpg.
Thanks guys!
Pro
Joined: Jul 2011
Posts: 608
Likes: 17
From: South Lyon, MI
I had heads, intake manifold, throttlebody, fuel rails, and injectors all done, plus an updated tune. I just mentioned injectors because I figure that was the one thing directly related to raw fuel consumption. Is the duty cycle you're referring to something that would need to be changed during a tune with this many component changes? Or is it possible it was skipped?
Thanks guys!
Thanks guys!