Huge Sudden drop in gas mileage SOLVED
07-08-2011, 11:47 PM
#33
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Year: 1996
Model: Cherokee
Engine: 4.0 HO
MPG ???
The 96 Cherokee SE 2-dr. is my first Jeep, bone stock 2wd 4.0 HO with auto tranny. A/C blows ice cubes, no cruise control.
Somewhere in reading up, I read that this setup is supposed to get 22mpg highway,,, don't remember where.
With a dirty air filter and plugged up converter, I got 17.7 out of my first tank.
New converter, updated computer flash, new air filter, and running some Seafoam in this tank, I'm interested to see what the beastie does now. Not going to run miles just for grins right now, the price of gas has jumped 9-11 cents in the last 2 days here (*%#@^%%*???&&&##)!
Related news info...
Congress voted this week to end the ethanol subsidy!!! I think it finally dawned on them that it takes more than one gallon of dino fuel (equivalent, regardless of energy source) to make one gallon of ethanol.
Also, it has become painfully obvious to the powers-that-be that it takes a flexfuel vehicle to run more than a 10% ethanol mix, which lets out the 15% mix. Rubber parts failure would happen much more quickly than the valve degradation that happened to leaded-gas cars when lead was taken out of gasoline . And yes, I'm old enough to remember that.
Somewhere in reading up, I read that this setup is supposed to get 22mpg highway,,, don't remember where.
With a dirty air filter and plugged up converter, I got 17.7 out of my first tank.
New converter, updated computer flash, new air filter, and running some Seafoam in this tank, I'm interested to see what the beastie does now. Not going to run miles just for grins right now, the price of gas has jumped 9-11 cents in the last 2 days here (*%#@^%%*???&&&##)!
Related news info...
Congress voted this week to end the ethanol subsidy!!! I think it finally dawned on them that it takes more than one gallon of dino fuel (equivalent, regardless of energy source) to make one gallon of ethanol.
Also, it has become painfully obvious to the powers-that-be that it takes a flexfuel vehicle to run more than a 10% ethanol mix, which lets out the 15% mix. Rubber parts failure would happen much more quickly than the valve degradation that happened to leaded-gas cars when lead was taken out of gasoline . And yes, I'm old enough to remember that.
07-08-2011, 11:54 PM
#34
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Year: 1996
Model: Cherokee
Engine: 4.0 HO
That's part of why only flexfuel vehicles are supposed to run E85, they are programmed to sense and adjust for the difference. In addition to rubber parts that will withstand E85...
07-09-2011, 12:12 AM
#35
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Year: 1994
Model: Cherokee
Engine: 4.0 L/242 CID I-6 High Output MFI
Unfortunately, Shell in my part of central TX has started selling 10% Eth gas.
The sale of this stuff also partly depends on the clean air rating for a metro area.
BTW, Hi! This is my first post here. I bought my 96 Cherokee SE 2 weeks ago and have fallen firmly in love with it. At 96k miles, I plan to be driving this gem a loooong time.
The sale of this stuff also partly depends on the clean air rating for a metro area.
BTW, Hi! This is my first post here. I bought my 96 Cherokee SE 2 weeks ago and have fallen firmly in love with it. At 96k miles, I plan to be driving this gem a loooong time.
Btw, I get 21 MPG on 93 octane. 202,236.4 miles on the clock.
Rob
07-09-2011, 07:54 AM
#36
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Year: 1997 & 1998
Model: Cherokee
Engine: 4.0
They're still pushing to change the blend ratio at the pumps to 15%. That will definitely trash our vehicles. Ethanol is corrosive to many of the components in the fuel systems of cars not made for multiple fuel types. All of our XJs were not made for this crap.
The person that mentioned BTUs as the reason that ethanol doesn't work like gasoline was correct. Ethanol has a significantly lower BTU rating than gasoline. It takes more ethanol to do the same work as gasoline. There's no way that a conventional engine would get the same mileage on ethanol than gasoline. In fact, if they did away with the blending all together, we all would see an improvement in performance as well as mileage.
We recently traveled through Wisconsin, Minnesota and Iowa with my F-150 and 24' travel trailer. The fuels there were big with ethanol. I know for sure that I got even worse mileage than I get (you don't get anywhere near 10 mpg in a gas engined truck towing an RV under most any circumstances normally). That equated in more expense for the trip in the end and I'm quite sure that it did. The fuel was cheaper than it is here, but when you have to use much more of it, how does that make it a cheaper fuel alternative? You don't save that much money buying ethanol to make it worth the extra purchases needed to get the same distance.
Oh yeah....as a side note to the discussion brewing, I get 20 mpg fairly regularly with both of our XJs on 87 octane and did with the previous ones. The only mod done to them was replacing the air box with a cone filter. I recommend this mod.
The person that mentioned BTUs as the reason that ethanol doesn't work like gasoline was correct. Ethanol has a significantly lower BTU rating than gasoline. It takes more ethanol to do the same work as gasoline. There's no way that a conventional engine would get the same mileage on ethanol than gasoline. In fact, if they did away with the blending all together, we all would see an improvement in performance as well as mileage.
We recently traveled through Wisconsin, Minnesota and Iowa with my F-150 and 24' travel trailer. The fuels there were big with ethanol. I know for sure that I got even worse mileage than I get (you don't get anywhere near 10 mpg in a gas engined truck towing an RV under most any circumstances normally). That equated in more expense for the trip in the end and I'm quite sure that it did. The fuel was cheaper than it is here, but when you have to use much more of it, how does that make it a cheaper fuel alternative? You don't save that much money buying ethanol to make it worth the extra purchases needed to get the same distance.
Oh yeah....as a side note to the discussion brewing, I get 20 mpg fairly regularly with both of our XJs on 87 octane and did with the previous ones. The only mod done to them was replacing the air box with a cone filter. I recommend this mod.
Last edited by wjnfirearms; 07-09-2011 at 08:01 AM.
07-09-2011, 08:29 AM
#37
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Model: Cherokee
That said, you have to burn more of it due to BTU difference.
07-09-2011, 09:12 AM
#38
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Year: 1994
Model: Cherokee
Engine: 4.0L AMC 242
I hate to be the jackass here, but at least the HO AMC 242 was designed to handle E10 without an issue. I have ran my XJ on both E10 and straight up gas and no difference.
07-09-2011, 09:43 AM
#39
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Year: 1996
Model: Cherokee (XJ)
Engine: 4.Slow
Just for the record, why are we getting PO'ed about this? As long as it runs and gets you from point A to B does it matter if its E whatever or regular?
07-09-2011, 10:35 AM
#40
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Year: 1994
Model: Cherokee
Engine: 4.0 L/242 CID I-6 High Output MFI
Reading through the factory service manual, I learned that at least the 1994 model year is made to run on 10% ethanol.
07-09-2011, 11:13 PM
#42
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Year: 1992
Model: Cherokee
Engine: 4.0
Sounds like some of you are having decent resuslts with the 87 and even 91 blends. I stand corrected. It could be an altitude thing for me getting better mileage on the lower 85 blend (not E85). My cousin today told me he gets similar results up here on his XJ, decent mileage on 85 and poor mileage on the higher blends. Anyone know if this is an altitude thing? We are at about 6500ft.
BTW just installed my first lift kit today, 3" RC Series II w full leafs. Wow what a day! It looks great and is running well even at interstate speed.
BTW just installed my first lift kit today, 3" RC Series II w full leafs. Wow what a day! It looks great and is running well even at interstate speed.
07-09-2011, 11:45 PM
#43
Senior Member
I was under the impression that most vehicles made after 1990ish were all set up to run on E85 already? I dont remember where I saw/heard/read that, but I do remember seeing that somewhere.
But anyway, I have a hard time believing the the small blend would cause a 55% drop in miles per gallon. Does ANYONE believe that, except for the original poster?
But anyway, I have a hard time believing the the small blend would cause a 55% drop in miles per gallon. Does ANYONE believe that, except for the original poster?
07-10-2011, 12:06 AM
#44
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Year: 1994
Model: Cherokee
Engine: 4.0 L/242 CID I-6 High Output MFI
I was under the impression that most vehicles made after 1990ish were all set up to run on E85 already? I dont remember where I saw/heard/read that, but I do remember seeing that somewhere.
But anyway, I have a hard time believing the the small blend would cause a 55% drop in miles per gallon. Does ANYONE believe that, except for the original poster?
But anyway, I have a hard time believing the the small blend would cause a 55% drop in miles per gallon. Does ANYONE believe that, except for the original poster?
07-10-2011, 02:40 PM
#45
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Year: 1998 Classic
Model: Cherokee
Engine: 4.0
I have a 2007 F150 that is factory set up to run straight fuel, 10% mix or E85.
To buy E85 is about 20 cents less a gallon (at least in Katy, Texas it is). But, my mileage drops considerably, and the power drops too (you can feel the difference). After all is said and done, savings is about 20 cents a fillup (my truck holds 30 gallons). I learned real qiuck not to use the E85 when towing. Then you really feel a difference with a Jeep on a trailer in tow. It is priceless to get the stares as you put the bright green hose in your fill up spout.
I write down every fill up on an excel spreadsheet, so yes, I have all the mileage and cost numbers.
I was under the impression E85 was supposed to be a stop gap between normal gas vehicles and the future vehicles. But all it seems to be doing is driving the price of food up (please let me know when you find something which does not have corn syrup in it).
Yes, the altitude does make a definite difference. If you ever go to sea level, bring a five gallon can of the 85 octane fuel along. Dump it in when your at sea level and watch the performance of your Cherokee go way down and the detonation (knocking) go way up. I have forgotten the reasoning behind the lower octane working at high elevations, but it does matter.
To buy E85 is about 20 cents less a gallon (at least in Katy, Texas it is). But, my mileage drops considerably, and the power drops too (you can feel the difference). After all is said and done, savings is about 20 cents a fillup (my truck holds 30 gallons). I learned real qiuck not to use the E85 when towing. Then you really feel a difference with a Jeep on a trailer in tow. It is priceless to get the stares as you put the bright green hose in your fill up spout.
I write down every fill up on an excel spreadsheet, so yes, I have all the mileage and cost numbers.
I was under the impression E85 was supposed to be a stop gap between normal gas vehicles and the future vehicles. But all it seems to be doing is driving the price of food up (please let me know when you find something which does not have corn syrup in it).
Yes, the altitude does make a definite difference. If you ever go to sea level, bring a five gallon can of the 85 octane fuel along. Dump it in when your at sea level and watch the performance of your Cherokee go way down and the detonation (knocking) go way up. I have forgotten the reasoning behind the lower octane working at high elevations, but it does matter.
Last edited by XJ Rat; 07-10-2011 at 02:45 PM.
