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No MPG Boost tune?

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Moderator: sohfast94

Post Sun Dec 02, 2018 10:19 pm

Posts: 9
am i correct in understanding that i dont get an "MPG boost tune" because my truck is 2004? :(

so far i am down in MPG... a lot...

Post Mon Dec 03, 2018 9:13 am

Posts: 53925
Location: DiabloSport World Headquarters

Yeah, wasnt much to improve on them like the newer trucks with AFM...but nothing in the tune will cause a drop.

Was your speedo off before you loaded the tune?
if so, you can compare MPGs before and after correcting the speedo...
Mike Litsch
Powerteq Customer Service Manager
Diablo Tech support by phone:
561-908-0040x4
M-F 8:00 AM to 5:00 PM EST

Post Tue Dec 04, 2018 11:00 am

Posts: 9
The 87 tune killed my mpg


Stock gears.
I changed to 285/75R16 tires immediately.
Stock was 265/75R16

When i do my MPG id add 10% to the odometer and cross reference that number against google maps.

The Diablo tuner now gets me 16mpg highway....
My 1987 4x4 got that

I uninstalled the 87 tune and just did the tire size and transmission shift mods. So we will see.

$360 to adjust tire size and change shift points.....

And this morning the speedometer was 5mph off. according to the school zone radar sign

Post Wed Dec 05, 2018 11:12 am

Posts: 53925
Location: DiabloSport World Headquarters

I dont think you can properly correlate the MPGs before and after the tire size change in that manner.
Mike Litsch
Powerteq Customer Service Manager
Diablo Tech support by phone:
561-908-0040x4
M-F 8:00 AM to 5:00 PM EST

Post Wed Dec 05, 2018 12:26 pm

Posts: 9
No, im saying these tires have been on the truck since i have owned it.

It got 17 now it gets 12.

I uninstalled the tune so soon we will know of its back to 17.

Point is... it killed my millage.
Probably gonna return it unless i can get a tune that works :(

Post Thu Dec 06, 2018 10:53 am

Posts: 17340
Location: CT

well, the preset canned tunes do not change any airflow or fueling settings at all... so the tune is not causing it really... plus, after installing a tune, everything gets reset and it takes days/150+ miles to be put on for everything to get relearned by the PCM and settle back in again.. and the mileage info in the DIC will not be correct for a while...
06MonteSS / DiabLew Tune
Image
2014 Camaro SS - 2SS, RS pkg., short-throw shifter, NPP perf. exhaust, BMR strut-tower brace, Cold Air Inductions cold air intake
www.diablewtune.com -- www.diablocustomtune.com -- www.diablocustomtunegm.com -- www.diablocustomtuning.net

Post Thu Dec 06, 2018 11:12 am

Posts: 9
This was done over 2 tanks of fuel.
Usually a tank lasts me over 300miles (without actually going empty)
The diablo tune drained 22 gallons in almost 200 miles.
So the MPG gains are a lie. Fake news lol
That was the whole reason i bought this thing.

Now its got a problem with the brakes where it pulls right..... into the gas station.


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