Improving mileage... - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep Grand Cherokee & Commander Forums > ZJ Grand Cherokee Forum > Improving mileage...

Alloy USA and Posi-Lok Cable Axle Disconnect Kits Dana 30 Stainless Steel Door Hinge PinsPoly Door Hinge Bushings

Reply
Unread 06-18-2011, 01:54 PM   #1
RoyalT1992
Registered User
1995 ZJ 
 
Join Date: Jun 2011
Location: Conifer, CO
Posts: 6
Improving mileage...

Hey folks, this is my first post. I drive 95 Grand Cherokee Orvis, it's awesome but has given me plenty of trouble.
I'm currently trying to imrove my mileage because a trip from my house to Denver and back costs $20 and I make the trip quite frequently. I'm looking at cold air intakes right now, and I'm leaning more towards the Rugged Ridge because of the dry flow filter, whereas the K&N has to be oiled. any thoughts?
What about throttle body spacers?
Or removing the rails that go across my roof? i heard it would help, but significantly?

RoyalT1992 is offline   Reply With Quote
Unread 06-18-2011, 02:17 PM   #2
808Defender
Registered User
2000 WJ 
 
Join Date: Mar 2011
Location: Honolulu Hawaii/, Seattle Washington
Posts: 504
It wont help much i pulled both of mine to the back have not noticed much. You can also just go with a K&N filter it will help some. do a basic tune up. I know Accell has a good package get new wires distributor and plugs.
808Defender is offline   Reply With Quote
Unread 06-18-2011, 02:26 PM   #3
MilwaukeeZJ
Registered User
1998 ZJ 
 
Join Date: Feb 2011
Location: Milwaukee, WI
Posts: 40
balls out tuneup. plugs wires cap rotor air and oil filters. keep your windows shut and use a/c on low setting. and keep your foot off the gas. use cruise on the freeway. drive the speed limit. wear your seat belt. i do all of this and i'm at 18.7 avg for the week. i reset it weekly to see if it fluctuates. but most importantly drive the speed limit. you use about half of the power your car makes overcoming air resistance, and when you go faster, that goes up.
__________________
AIM: imeffindash
twitter: @PapaTonyTheDon
email: thisisawrittenthreat@gmail.com
i love my jeep, hookah, and women. :D
MilwaukeeZJ is offline   Reply With Quote
Unread 06-18-2011, 02:48 PM   #4
RoyalT1992
Registered User
1995 ZJ 
 
Join Date: Jun 2011
Location: Conifer, CO
Posts: 6
Hm. My buddy put the cold air in his 98 cherokee sport and it upped his mileage 2 or 3. If it does that for mine, I'm down cause it'll put me over 20 mpg. I recently put in a cat-back exhaust because i didn't have a tailpipe for a while, it put me from 14.5 to 17.2. How much will the wires and distributor help? most of my driving is highway and i use my cruise control as much as possible. Thanks for the help guys
RoyalT1992 is offline   Reply With Quote
Unread 06-18-2011, 05:38 PM   #5
gothchick
Registered User
1998 ZJ 
 
Join Date: Jul 2010
Posts: 702
The Dodge Neon fuel injector swap seems to be promising, in addition to free flow intake and exhaust.
__________________
Don't fear the regear.

Finished 4x2 --> 4x4 conversion.
gothchick is offline   Reply With Quote
Unread 06-18-2011, 05:52 PM   #6
TallyZJ
Registered User
1996 ZJ 
 
Join Date: Nov 2008
Location: Tallahassee, Florida
Posts: 1,140
Quote:
Originally Posted by gothchick View Post
The Dodge Neon fuel injector swap seems to be promising, in addition to free flow intake and exhaust.
I gained nothing with the injector swap. I also have the 2001 large volume intake manifold, WJ intake air hat (plenum), 52mm bored throttle body, removed the intake hose air horn obstruction and none of this really made a difference in mileage.

My biggest gains came from a good complete tune up, cleaning the throttle body, replacing all the sensors (TPS, CPS, MAP and AIT), replaced both O2 sensors with Mopar OEM units, a new clean air filter and using good control on the skinny pedal.
__________________
1996 Jeep Grand Cherokee Laredo 4x4 - 4.0L
Capital City Jeepers
Build Thread Here
TallyZJ is offline   Reply With Quote
Unread 06-18-2011, 06:37 PM   #7
blackjack12982
Web Wheeler
 
blackjack12982's Avatar
1994 ZJ 
 
Join Date: Mar 2009
Location: Cunningham, TN, Tennessee
Posts: 1,879
Quote:
Originally Posted by TallyZJ View Post
My biggest gains came from a good complete tune up, cleaning the throttle body, replacing all the sensors (TPS, CPS, MAP and AIT), replaced both O2 sensors with Mopar OEM units, a new clean air filter and using good control on the skinny pedal.
^ This!
__________________
Want to do an Aurora reverse light swap? Need a 231/242 bezel? Need a Taurus efan? See the ad below

http://www.jeepforum.com/forum/f130/...ights-2342649/
blackjack12982 is offline   Reply With Quote
Unread 06-18-2011, 07:41 PM   #8
gothchick
Registered User
1998 ZJ 
 
Join Date: Jul 2010
Posts: 702
Quote:
Originally Posted by TallyZJ View Post
I gained nothing with the injector swap. I also have the 2001 large volume intake manifold, WJ intake air hat (plenum), 52mm bored throttle body, removed the intake hose air horn obstruction and none of this really made a difference in mileage.

My biggest gains came from a good complete tune up, cleaning the throttle body, replacing all the sensors (TPS, CPS, MAP and AIT), replaced both O2 sensors with Mopar OEM units, a new clean air filter and using good control on the skinny pedal.
Seriously on the injectors??? Sorry to hear. Damn... I was really hopeful about that mod too...
__________________
Don't fear the regear.

Finished 4x2 --> 4x4 conversion.
gothchick is offline   Reply With Quote
Unread 06-18-2011, 08:08 PM   #9
TallyZJ
Registered User
1996 ZJ 
 
Join Date: Nov 2008
Location: Tallahassee, Florida
Posts: 1,140
Quote:
Originally Posted by gothchick View Post
Seriously on the injectors??? Sorry to hear. Damn... I was really hopeful about that mod too...
All I noticed was a better smoother idle with the new injectors. Even that wasn't worth the swap really except that the injectors cost me nothing. If I had to pay for them I would not have even swapped knowing what I know now.

Its something to do, something to modify and tinker with that doesn't hurt anything so its not a total loss. People want to believe these things improve mileage, power and torque but they really don't do much at all.

If you did these mods, along with the addition of porting the head, flow matching the ports, new camshaft, roller rockers, good exhaust header, good exhaust system, a power tuner blah blah, then all collectively together you would see a good power and torque gain.

Neon, Stratus or Ford injectors do not really push that much more fuel, if any, into the combustion chamber. Without the other extensive mods the computer system will compensate and change the fuel mixture to achieve the appropriate ratio. The only benefit of the new injectors is their four hole spray tip which might, I say might, provide better spray pattern for a slightly better/faster burn.

None of this matters if you can't get a lot more air (exhaust) out of the engine. It can only pass so much so attempting to take more air and fuel in does nothing. You would probably see the same gains with nothing more than a good efficient complete exhaust system and air intake modifications.
__________________
1996 Jeep Grand Cherokee Laredo 4x4 - 4.0L
Capital City Jeepers
Build Thread Here
TallyZJ is offline   Reply With Quote
Unread 06-19-2011, 01:43 AM   #10
Candymancan
Registered User
1998 ZJ 
 
Join Date: Aug 2010
Location: Virginia
Posts: 3,816
Does driving with the a/c on say in the city really help gas mileage vs having the door windows down ? I can understand on the freeway yea but in the city ? Stop and go, it seems while being at stop lights and such the a/c would actually run the gas mileage up vs just suffering in the heat.

I try my best to get the most outa my tank as i can, turning the engine off when i get outa the car, driving the speed limit, cruise control when i come to long roads, make sure the engine is clean. My computer says 12.6mpg, but last i checked ( cant afford full tank fillup's right now..cough $100) i was actually getting 13.6-14mpg. Is it really worth replacing all that junk mentioned above... tps, o2 sensors ect ect.. I know my spark plugs are clean i checked em, and the throttle body has been cleaned awhile back, and i have new air filter on there, im sure the o2 sensor are original.. and i dont have a plenum leak or anything. But i guess since im getting average 13mpg in the city then there is probably nothing else i could do anyway as thats normal for a 5.9

Only thing i hate about owning a Jeep I6 or 5.9 alike is both get bad gas mileage and both unless your rich, it holds you back from really just driving around or possibly wanting to take a trip somewhere over the weekand. Were going to a short vacation here in a few hours to nags head beach in North Carolina and the trip is 520 miles round trip, not counting where ever we drive to check out places.. its a good thing we have the 4.0 at least that gets like 20ish mpg on the freeway.

Altho if you have to drive 64miles to and from work everyday even 19-20mpg the gas is gone in a week, not counting having to run errands and stuff.. We spend a g ood $330 a month on gas for just the 4.0, and the 5.9 is around $150-200 as it isnt driven as much
__________________
2013 6.2 V8 Camaro SS 4k miles
1998 5.9 V8 ZJ 160k miles
1998 4.0 I6 Laredo ZJ 210k miles
Candymancan is offline   Reply With Quote
Unread 06-19-2011, 02:21 AM   #11
Andy05
Registered User
1997 ZJ 
 
Join Date: Apr 2011
Location: tucson, az
Posts: 87
wow, Im getting 16.2 in a stock 97 GC 4.0l. All city. I guess Im just one of the lucky ones.
Andy05 is offline   Reply With Quote
Unread 06-19-2011, 02:26 AM   #12
Candymancan
Registered User
1998 ZJ 
 
Join Date: Aug 2010
Location: Virginia
Posts: 3,816
Quote:
Originally Posted by Andy05 View Post
wow, Im getting 16.2 in a stock 97 GC 4.0l. All city. I guess Im just one of the lucky ones.
Im talking my 5.9 our 4.0 gets around the same city 16.


Plus city's are different, we could have more stop lights then you, or more traffic ect
__________________
2013 6.2 V8 Camaro SS 4k miles
1998 5.9 V8 ZJ 160k miles
1998 4.0 I6 Laredo ZJ 210k miles
Candymancan is offline   Reply With Quote
Unread 06-19-2011, 05:00 AM   #13
Andy05
Registered User
1997 ZJ 
 
Join Date: Apr 2011
Location: tucson, az
Posts: 87
Well the OP was talking about a 4.0.
I work 6 miles form home, 40 mph speed limit. And have 6 stop lights and four stop signs on the way. Being 2wd helps alot I'm sure.
My weekend worrior only gets 12.7 city and highway lol, so Ill take 16 any day.
Andy05 is offline   Reply With Quote
Unread 06-19-2011, 05:02 AM   #14
MilwaukeeZJ
Registered User
1998 ZJ 
 
Join Date: Feb 2011
Location: Milwaukee, WI
Posts: 40
Quote:
Originally Posted by Candymancan View Post
Does driving with the a/c on say in the city really help gas mileage vs having the door windows down ? I can understand on the freeway yea but in the city ? Stop and go, it seems while being at stop lights and such the a/c would actually run the gas mileage up vs just suffering in the heat.

I try my best to get the most outa my tank as i can, turning the engine off when i get outa the car, driving the speed limit, cruise control when i come to long roads, make sure the engine is clean. My computer says 12.6mpg, but last i checked ( cant afford full tank fillup's right now..cough $100) i was actually getting 13.6-14mpg. Is it really worth replacing all that junk mentioned above... tps, o2 sensors ect ect.. I know my spark plugs are clean i checked em, and the throttle body has been cleaned awhile back, and i have new air filter on there, im sure the o2 sensor are original.. and i dont have a plenum leak or anything. But i guess since im getting average 13mpg in the city then there is probably nothing else i could do anyway as thats normal for a 5.9

Only thing i hate about owning a Jeep I6 or 5.9 alike is both get bad gas mileage and both unless your rich, it holds you back from really just driving around or possibly wanting to take a trip somewhere over the weekand. Were going to a short vacation here in a few hours to nags head beach in North Carolina and the trip is 520 miles round trip, not counting where ever we drive to check out places.. its a good thing we have the 4.0 at least that gets like 20ish mpg on the freeway.

Altho if you have to drive 64miles to and from work everyday even 19-20mpg the gas is gone in a week, not counting having to run errands and stuff.. We spend a g ood $330 a month on gas for just the 4.0, and the 5.9 is around $150-200 as it isnt driven as much
the window/ac thing is mostly freeway, i dont take my jeep on city streets cuz stoplights kill me haha
__________________
AIM: imeffindash
twitter: @PapaTonyTheDon
email: thisisawrittenthreat@gmail.com
i love my jeep, hookah, and women. :D
MilwaukeeZJ is offline   Reply With Quote
Unread 06-19-2011, 05:35 AM   #15
coralman
green backs to no backs
 
coralman's Avatar
1998 ZJ 
 
Join Date: Jul 2010
Location: florida
Posts: 4,438
Stop and go destroys the I6 mileage hands down. In most of the injector swap original posts they never said anything sbout significant mileage gains that I read. It was mostly about improved idle and maybe alittle more giddyap. I have a cracked exhaust {who doesn't} and for the heck of it figured I would do the mods as well.

The manifold shifts the power curve lower alittle bit over the straight runners, and as tally said without other mods will show no significant mph gain. I am installing a complete magnaflow exhaust soon and figured while I was in there...

Sensor quality, air filter, and cap rotor and wires have given me the most gain. Wires go to crap with the underhood heat of zj's, and I replace them often. Believe it or not a $30 set of denso wires have been really good.
coralman is offline   Reply With Quote
Reply
Thread Tools


Suggested Threads





Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.