Horrible gas mileage.! Whhyyyyyyy - Page 2 - Ford Mustang Forum
Reply
 
LinkBack Thread Tools
PONY Member
 
psycho bob's Avatar
 
Joined: Apr 2012
Location: Peyton
Posts: 429
 
when i changed my diff fluid i immediately got better mpg. i didn't think there was any way simply changing that would be significant, but it was. if you're using the stock diff i'd go with a synthetic gear oil. i never did alot of research on the different weights of the fluid. i really can't remember which one i used either.


Heads, Cams, Edelbrock Eforce, 4.10 & true-trac, TR6060 trans, DSS driveshaft, Full BMR suspension, tokico d-specs, eibach pro kit springs
psycho bob is offline  
Sponsored Links
Advertisement
 
Registered User
 
Brenspeed's Avatar
 
Joined: Jul 2005
Location: North Webster
Posts: 1,910
 
The tune runs more timing and a leaner A/F than the factory tune, so I highly doubt its the tune. Our tune does not cater to gas mileage, but it certainly shouldnt get any worse than your factory tune by a mile per gallon or two. It can come down to the quality of gas you are getting, does it contain ethanol? When is the last time you replaced your fuel filter? There are many variables that come into play when you are talking gas mileage. I tell everyone this, the tune doesnt change. How long have you been running our tune? If the gas mileage all of a sudden gets worse, then something is going on mechanically with the car that needs to be addressed. Please feel free to call me directly at 574.594.9559 ext 3 if you would like to talk more about this. Hope this helps.

Thanks,
Chandler

Brenspeed is offline  
Apprentice
S197 Member
 
Beastiezzz's Avatar
 
Joined: Dec 2004
Location: Staten Island
Posts: 130
 
It's possible that there is ethanol in my gas, I'll have to look into that. I've done all of the general maintenance that we can come up with on here, clean tb, clean CAI and MAF sensor, fuel filter, and even spark plugs with no improvement. I've just been at a loss trying to find something else that would affect it...I didnt think the tune could change out of nowhere but I'm all out of ideas...would ethanol really screw things up that much?

2005 Mustang GT, C&L street CAI with brenspeed tune, pypes mid-muffler cat back exhaust, and a cervini's shelby style hood.
Beastiezzz is offline  
 
post #19 of 27 (permalink) Old 06-15-2012 Thread Starter
PONY Member
S197 Member
 
s197fordgt's Avatar
 
Joined: Jan 2012
Location: port orange
Posts: 291
 
The tune runs more timing and a leaner A/F than the factory tune, so I highly doubt its the tune. Our tune does not cater to gas mileage, but it certainly shouldnt get any worse than your factory tune by a mile per gallon or two. It can come down to the quality of gas you are getting, does it contain ethanol? When is the last time you replaced your fuel filter? There are many variables that come into play when you are talking gas mileage. I tell everyone this, the tune doesnt change. How long have you been running our tune? If the gas mileage all of a sudden gets worse, then something is going on mechanically with the car that needs to be addressed. Please feel free to call me directly at 574.594.9559 ext 3 if you would like to talk more about this. Hope this helps.



To be honest. This has happened since I put the tune in the car. There might have been a mix up with the specifics of the tune. During that time I think the jlt series 3 was coming out and I had the series 2. I did not know about the series 3 until after I purchased the tune and did not specify what series I had. Could this be the problem?

Cherry, 05 mustang gt Black, w/red leather, AUTO
RZ pro speed 20" concave wheels
Sct tuner w/Brenspeed 93,89 and 87.
Jlt cold air intake, Mac prochamber with slp loudmouths, Drop zone lowering springs and a stallion on car adjustable panhard bar.
Ran a best of 13.343 @ 102.70, 60' 2.053. (On street tires)
s197fordgt is offline  
Registered User
 
Brenspeed's Avatar
 
Joined: Jul 2005
Location: North Webster
Posts: 1,910
 
Generally the ethanol is only a 10% blend, so it really shouldnt effect things that much (maybe a mpg or two). How long have you had those wheels, because those wont help your MPG. There are SOOOO many variables that come into play, you literally have to think of everything.

Chandler
Brenspeed is offline  
PONY Member
 
mustangdave2008's Avatar
 
Joined: Sep 2009
Location: Granite Falls
Posts: 412
 
If it started when you loaded the tune, then the tune is the problem. Have you tried reloading the tune? Are you sure you loaded the Brenspeed tune and not one of the SCT tunes? Did you update the tuner first and follow all steps for loading tune? It's very easy to make a mistake; guilty myself.

JLT series 3 c.a.i., detroit rocker cams, various tunes, roush front fascia w/chin spoiler.
mustangdave2008 is offline  
ski
GT Member
S197 Member
 
ski's Avatar
 
Joined: Dec 2004
Location: Northeast
Posts: 1,653
 
Some other possible causes of poor gas mileage are dragging brakes, clogged cat, and faulty coolant temperature sensor(ECU stays in open loop mode).
ski is offline  
post #23 of 27 (permalink) Old 06-15-2012 Thread Starter
PONY Member
S197 Member
 
s197fordgt's Avatar
 
Joined: Jan 2012
Location: port orange
Posts: 291
 
The car has had these wheels since I owned it. Yes I know there is the tuners tunes and custom tunes. I am not oblivious to the tuners interface. Like I asked before. I'm wondering if it's because I did not specify which jlt series I had?

Cherry, 05 mustang gt Black, w/red leather, AUTO
RZ pro speed 20" concave wheels
Sct tuner w/Brenspeed 93,89 and 87.
Jlt cold air intake, Mac prochamber with slp loudmouths, Drop zone lowering springs and a stallion on car adjustable panhard bar.
Ran a best of 13.343 @ 102.70, 60' 2.053. (On street tires)
s197fordgt is offline  
PONY Member
 
psycho bob's Avatar
 
Joined: Apr 2012
Location: Peyton
Posts: 429
 
chandler (brenspeed rep) gave you his number. call him directly and have him look to see which JLT they used for the tune. obviously it is the tune if you didn't do anything else and it immediately was that much worse.

w/ a jlt cai & bama tune i didn't loose any mpg at all.

Heads, Cams, Edelbrock Eforce, 4.10 & true-trac, TR6060 trans, DSS driveshaft, Full BMR suspension, tokico d-specs, eibach pro kit springs
psycho bob is offline  
post #25 of 27 (permalink) Old 06-16-2012 Thread Starter
PONY Member
S197 Member
 
s197fordgt's Avatar
 
Joined: Jan 2012
Location: port orange
Posts: 291
 
I called them earlier and was told I had to wait until next week to see what intake was on the tune.

Cherry, 05 mustang gt Black, w/red leather, AUTO
RZ pro speed 20" concave wheels
Sct tuner w/Brenspeed 93,89 and 87.
Jlt cold air intake, Mac prochamber with slp loudmouths, Drop zone lowering springs and a stallion on car adjustable panhard bar.
Ran a best of 13.343 @ 102.70, 60' 2.053. (On street tires)
s197fordgt is offline  
Registered User
 
Brenspeed's Avatar
 
Joined: Jul 2005
Location: North Webster
Posts: 1,910
 
If the tune was setup for a JLT series 2 and you have a JLT series 3, you would literally know it the minute you started the car, because it would barely want to start and bog right when you tried to give it throttle. Basically, if it was setup for the wrong CAI you would know it and would have called right after the tune loaded on. Give me a call on Monday when the tuner gets back into town and I will be more than happy to look into the tune for you. I can be reached directly at 574.594.9559 ext 3.

Thanks,
Chandler
Brenspeed is offline  
PONY Member
 
GTDanny's Avatar
 
Joined: Dec 2009
Location: Blythewood
Posts: 320
 
I have had Diablospert canned tunes , Brenspeed email tunes and now I have a custom dyno tune from Dan @ Prodyno and I have aways gotten BETTER gas milage with all there tunes...

I WISH I COULD GET RID OF THE KNOCKING NOISE IN MY FRONT END. I'M TIRED OF SPENDING MONEY ON IT... IT'S DRIVING ME CRAZY!!!!!!!!!!!!!!!!!!!!!!
GTDanny is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Ford Mustang Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a VALID email address for yourself, otherwise you will not receive the necessary confirmation email needed to confirm, validate and activate your new AFM member account.

Failure to provide a VALID email address, will result in the cancellation of your new AFM member account registration.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome
 


Search Engine Friendly URLs by vBSEO 3.6.1