What is wrong?

Bobbyo · 11-25-2005, 09:24 AM

Hello folks and happy Holidays,

I have had my 04 titain for one year now,4X4 Big tow, off road, crew cad. Have keep records of all my gas fill ups. I drive 350 miles per week 60 % highway 40% around town.When I first got the truck average miles 12.5 pg then as time went by and more miles on the truck , now 15,000 miles and all sinthetics can average 15.3 to 14.5 miles per gallon.
I installed a Gibson dual sport at 7000 miles and have the Air Hog filter.
Always wanted a truck and chose the titan over the big three because its just the best half ton out there.
Love this truck, so I figure I'm going to own this for a long time, so I might as well try to get the best milage possible, run at 60 ,65 miles an hour with the cruise control on.Air pressure on all tires 39 psi.
My next step was to install the AFE magnum stage 2 air system. This was done last week, I did the ECU reset , disconnecting the negitive battery post for 14 hrs. On my first tank of gas the milage has dropped off significantly, I will only get 12.5 mpg on this tank. Dont get me wrong I know its a truck and we won't get great gas milage, and some of the guys will say if your worried about mileage go buy a civic but these modifications should help bump up the milage. Not bring it down!!
So what do you guys think? Not enough time on the ECU reset? Sorry for the long winded story but very disapointed in the numbers, had hoped to gain maybe .5-1.0 miles pg more. Then get the bed cover.
Yes there is a huge difference on the low end torque, stepped on it 1 time to see the change then settled down to check the milage.
Thanks for any feed back
Bobbyo

baseballfanz · 11-25-2005, 09:36 AM

Why don't you try doing the ECU reset by the step listed instead of dis-connecting the battery cable.
ECU reset
That way you know if it's been reset or not. When I first got my Titan I was avg. 14 MPG been down to 12 MPG after a few months and have not gone back up.

Bobbyo · 11-25-2005, 10:01 AM

I tried the ECU reset that way and could not get the CEL to come on.

baseballfanz · 11-25-2005, 10:46 AM

Quote:

Originally Posted by Bobbyo

I tried the ECU reset that way and could not get the CEL to come on.

Try starting out in the "ACC" position instead of the "OFF" position. Took me a few try but on the first attempt from the "ACC" I got it. Now I do it every 2 week or so and get it everytime.

TOK · 11-25-2005, 11:02 AM

Not sure where you're located, but many states start using oxygenated fuels in November. I don't even track my mileage that close, and notice it gets worse when they start selling that stuff.

gtbaldini · 11-25-2005, 11:07 AM

I did the manual ecu reset via the gas pedal and my gas mileage went down a couple gallons as well. However, I also installed the banks and my foot has been permantly glued to the floor ever since. Since the reset helps regain performance it may also affect the mileage in a negative way. Dont know for sure, just a guess.

CHEIF · 11-25-2005, 11:31 AM

Can't help but ask. It only makes sense to me. If you install an intake to put more air in, then you will need more fuel to keep a good mixture ratio. Even if you alter what the ECU reads, you will need more gas, not less. Has anyone ever gotten better mileage with less restriction either in, out or both??? I wouldn't expect it.

I've noticed my mileage drop from about 15 to 12.5 with the colder weather, it could be the gas, but it's also more Oxygen in the air, which will cause the ECU to feed more fuel into the mix and maintain the same oxygen to fuel ratio.

It's very noticeable on a 2 stroke engine. I needed 3 sets of jets to run year round on my last dirtbike. One set for summer, winter, and the transitions.

Cheif

Bobbyo · 11-25-2005, 11:36 AM

Just tried ACC position still no luck!!

bestatchess · 11-25-2005, 11:38 AM

Quote:

Originally Posted by CHEIF

Can't help but ask. It only makes sense to me. If you install an intake to put more air in, then you will need more fuel to keep a good mixture ratio. Even if you alter what the ECU reads, you will need more gas, not less. Has anyone ever gotten better mileage with less restriction either in, out or both??? I wouldn't expect it.

I've noticed my mileage drop from about 15 to 12.5 with the colder weather, it could be the gas, but it's also more Oxygen in the air, which will cause the ECU to feed more fuel into the mix and maintain the same oxygen to fuel ratio.

It's very noticeable on a 2 stroke engine. I needed 3 sets of jets to run year round on my last dirtbike. One set for summer, winter, and the transitions.

Cheif

My MPG is down by about 1 mpg. I attributed it to snow tires plus whatever crap they put in the winter gas to keep the air cleaner.

Treebasher · 11-25-2005, 01:49 PM

Quote:

Originally Posted by bestatchess

My MPG is down by about 1 mpg. I attributed it to snow tires plus whatever crap they put in the winter gas to keep the air cleaner.

It's that time of year again. Not only do some of us get a different blend of petro but it takes the engine a bit longer to get to optimal operating temperatures. Short trips in the winter can really give you some crappy gas mileage. I'm down about 1 mpg or so as well.

Keep trying Bobbyo. It takes a few tries the first time.

Bobbyo · 11-25-2005, 02:28 PM

I understand that the fuel blend is different this time year and can cause a drop in mileage. but what I find troubling is the milage droped as soon as I installed the AFE stage 2 l

Vyrus · 11-25-2005, 06:45 PM

Bobbyo my mileage has also dropped recently, it was defintely due to the gas blend. I'll bet that's your problem also, but go ahead and try the ECU reset the manual way to be sure. The intake is a simple assembly, there's nothing you can do so wrong that your gas mileage would drop (well, you did screw the MAF back in right? haha j/k). I'm also getting around 12.5 mpg.
Good luck!
-Cyrus

Austin · 11-25-2005, 08:20 PM

Quote:

Originally Posted by Bobbyo

I understand that the fuel blend is different this time year and can cause a drop in mileage. but what I find troubling is the milage droped as soon as I installed the AFE stage 2 l

Winter fuel blends are a common reason to suffer a drop in mileage.

Also, your mileage didn't drop because you installed an intake - your mileage dropped because you reset your ECU, dropped all your fuel maps back to the base maps. Give it a tank or two to relearn the engine and your mileage should be back up to where it was before the reset.