Thanks all for your ideas. I have already tried many of them as part of my daily driving habits, such as coasting in neutral, not using heater/AC, etc. I have used seafoam on a number of occasions. I don't want to disconnect the front driveshaft, as I commonly use 4x4. I also don't have AAA and drive in very secluded areas so I don't want to take my spare out. I like the idea of the electric fan and timing advance. I would really like to find a way to remap my shift points and TC lockup speed. It seems like the engine "winds out" a little to fast for my taste with this type of driving. I've done a little looking on this forum about bored throttle bodies and newer style intake manifolds as well as Neon or Liberty fuel injectors. Can anybody give me some numbers as to how well they improve MPGs? This weekend I will be taking another long trip to northern WI. I'm going to try something drastic that I've read about on a number of occasions. I will fill the tank half with unleaded gas and half with E-85. I know, I know, bad Juju. But, I'v read that any vehicle with OBD I or OBD II can compensate for it and it's diluted enough that it won't hurt gaskets and whatnot. The worst that can happen is that it will dissolve deposits in my gas tank and clog my fuel filter. I'll give it a shot and see what happens. I know it probably won't improve my MPG but it should improve my MP$. I'll keep you posted.

 

I'm pretty sure that the e85 will actually hurt your MPG. Its got less octane and takes a little more fuel to get the same power. My grandma has a flex fuel van setup for e85 and she gets less miles out of a tank of e85 than regular unleaded.

My moms boyfriend filled up half tank with e85 by accident in a 98 Isuzu and it had the fuel system cleaned and a tunee up and it still doesn't run right.

It just doesn't sound like it would be worth the risk IMO. Let me know how it goes.

 

this. whenever I see a semi Im on them like a tick on a dogs ear.

I have heard it actually helps to leave it in gear, because the injectors will almost turn off.

 

any ethanol mix gas has less energy content which is why your car will lose mpg, doesnt have anything to do with the lower octane

ALSO I dont think a 4.0 jeep will run well on E85

 

I did some testing with full strength gasoline, E10 and E85. I made the same 250 mile trip once a week so I would run the truck empty and fill up with a different flavor of fuel each trip. I strongly suggest that you DO NOT run E85 in a vehicle not designed for it. Not only will they run like crap it can do some damage to your fuel system. From a strictly cost standpoint you get more bang (miles) for your buck from good ol' 100% gasoline. It's hard to find full strength gas anymore, I am lucky that the station down the street sells it. Costs a dime per gallon more but I usually pick up a couple miles per gallon so it is well worth the extra dime.

Electric fan, 0 weight crankcase oil, proper tire inflation and alignment, electric fan, smooth skid plates/belly armor, hydrogen blending (depending on the year of your car, some systems do not like hydrogen) are all cheap easy mileage assistants. The old put the car in neutral thing doesn't work, an idling engine uses more fuel than an engine being turned by the rotating mass of the transmission. Shutting the car off at stoplights isn't good either. Depending on the system, your vehicle may use several minutes worth of fuel at start up. Besides it's hard on everything to turn it on and off. Good luck on the 30MPG thing

 

Yea the Ethanol does not play well with the materials inside an older fuel system, even with some of the later ones for that matter.

There is a website that lists gas stations that still sell the real stuff.

http://pure-gas.org/

 

Not to be argumentative but E85 actually has significantly higher Octane at around 105. It also burns cooler saving stress on your engines components. That is assuming you are running at the right mixture. Which is where the real risk comes, in that my o2 sensor won't accurately compensate for the amounts of ethanol in the fuel and run too lean. Or that my injectors won't be able to keep up. Though, that would most likely only be an issue at WOT which I almost never run. Aside from that there isn't much risk of damage since all of the components are designed to handle some concentration of alcohol anyway. it really comes down to fuel management. Which is why E85 conversion kits consist of a piggyback computer and a set of injectors.

Alternately, I looked into the non-blended gasoline and I would only have to get 1-2 mpg more to make it pay out. Which, from my experience is not outside of reason.

 

well, counter to popular opinion, I ran 50/50 alcohol blend on my last long trip. I didn't hypermile as much as I did on my 25.6mpg run because I was short on time. Nothing bad happened. No check engine lights, no pistons launching through my hood. No leaks in the fuel system, just as I had researched. I did, as I expected, get lower mpgs. I got 21.5mpg. But again that was without any hypermiling. In addition my alternator went out on the trip so I spent a lot of time restarting and idling while I whacked my alternator with a wrench handle (got it to charge for another 30 miles per whack). The long and short of it is: with the 50/50 blend I was paying $0.165 per mile and with regular unleaded I was paying $0.150 per mile. I'm going to take a previous suggestion and run 100% gasoline, which is available at our corner gas station for about $0.15 more per gallon.

 

the neon injectors netted me .5 mpg increase.

ive heard of people using star tron fuel additive with success. it is made to put in fuel for boats, the ethanol wrecks havoc on boat motors. i have yet to try it.

i gained about 1.5 mpg when i found an ethanol free gas station. the fuel was a bit more pricey though.

i also gained 1.5 mpg from the addition of my snorkel.

i am stock other then the injectors, snorkel and cat back exhaust. im currently at 16 mpg with 170k miles, 3.55 gears and 33s.

 

Nix the power steering if your forearms are up to it. It's a constant drag...lower the jeep and put a lip spoiler on it...no fat chicks...keep your tank half full...replace side/rear glass with lexan...go on a diet...make sure your alignment is perfect...try 5w20 synthetic (less viscosity = less drag)...poop before you go on trips...keep your windows up...take everything out, except your spare...and still no fat chicks.

 

Always good advice with regards to fuel mileage or not... lol

 

It's my understanding that Fuel Injected engines cut the fuel off when your foot is off the peddle.
However, I do remember in the 70's during the start of the oil wars, doing that.

 

not true, the engine would die, especially in an auto where the torque converter would disengage

in an auto with the foot off the pedal the engine will just idle.

in a manual taking the foot off the pedal will cause engine braking, basically the wheels turning the engine, then yes the IAC will work and the injectors will be almost completely turned off.

 

SMALLER LIGHTER TIRE WHEEL COMBINATION PRIUS TIRE AND WHEEL WEIGHTS ABOUT 10LBS PER WHEEL

 

A renix cuts the injectors in deceleration until 1200 rpm...