Gas mileage fluctuation - 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 Wrangler Forums > YJ Wrangler Technical Forum > Gas mileage fluctuation

Introducing MONSTALINER™ UV Permanent DIY Roll On Bed LineFS: 2007-2013 Jeep Wrangler "HALO" Angel Eye KitFS: Wranger BRIGHT License Plate LED! Just $3! Great value

Reply
Unread 02-25-2009, 08:43 PM   #1
snaustin09
Registered User
 
Join Date: Nov 2008
Location: Central NY
Posts: 183
Gas mileage fluctuation

My gas mileage has fluctuated quite a lot lately: After a 200 mile round trip staying at around 55-60 on rt 20, I got 22 mpg, and when I filled up today I got a mediocre 12.5 mpg after 120 miles of around town driving. Now I know the 4.0 isn't a gas sipper, but this seems pretty low for a stock wrangler. Is this kind of fluctuation normal? I have heard people speak of staying in open loop or something during short around town trips (usual drives are about 4 miles), could this be my problem? I know I need to replace my O2 sensor, and possibly my CPS (CEL comes on after ~15 miles, then goes off). I have searched the forum and know that different wranglers can get very different mileage, just wondering why it seems to fluctuate so much, I am a very conservative driver.

__________________
"If the ladies don't find you handsome, they should at least find you handy" -Red Green
snaustin09 is offline   Reply With Quote
Unread 02-25-2009, 08:45 PM   #2
mattman320
Registered User
1995 YJ Wrangler 
 
Join Date: Jan 2009
Location: travelers rest, SC
Posts: 338
sittin in traffic KILLS MPG, doubt your o2 sensor has anything to do with it as i'm runni w/ no cat and gettin better than you are, what gear do you run in around town? i tend to shift very early (like around 1000) but thats with 33's also.
__________________
94 Red YJ, 2.5, 4.5" BDS lift, intake, exhaust, 33" Goodyear Wrangler Duratrac tires. I think i have the slowest car on the planet.
mattman320 is offline   Reply With Quote
Unread 02-25-2009, 09:08 PM   #3
Cross
Registered User
1991 YJ Wrangler 
 
Join Date: Jan 2007
Location: El Jebel, CO
Posts: 680
Are you buying gas at the same station every time? Some stations have ****ty gas. I easily get 200-250 miles a tank. Last week I filled up at a station I have never been to and got less than 200 highway miles in that tank. Went back to one of my normal gas stations and my mileage is back where it was.
Cross is offline   Reply With Quote
Unread 02-25-2009, 09:40 PM   #4
TA-YJ
Registered User
1992 YJ Wrangler 
 
Join Date: Dec 2007
Location: Pennsylvania
Posts: 517
If your O2 sensor is really shot than replacing it would give you better mileage. The CPS could also lead to lower mileage. I dont think either of these are the specific problem in this case though. I think its just going from all highway to driving in city. I usually get ~20mpg mixed, but when I only do city it drops to ~16.
TA-YJ is offline   Reply With Quote
Unread 02-25-2009, 09:48 PM   #5
rustywrangler
Got my eye on you.....
 
rustywrangler's Avatar
 
Join Date: Apr 2005
Location: Syracuse, NY
Posts: 18,612
Knowing where you are driving tells me alot. It is simply the city/highway issue. AND around here, some gas stations can kill your mileage and some are excellent. IT also has to do with the temp outside. I get crappy mileage when it is cold.

My other suggestion is to check your engine codes.
__________________

Congenital Heart Disease is a reality for me, BOTH of my children have it. Please read up and become aware for future generations

Lydia Ann-Acquired 08/05/05 Open Heart surgery 08/10/05
Jacob Patrick-Acquired 01/17/08 Open Heart surgery 02/15/08
rustywrangler 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.