Suggestions on how to improve fuel mileage? - GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat


1992-1999 Series I L27 (1992-1994 SE,SLE, SSE) & Series II L36 (1995-1999 SE, SSE, SLE) and common problems for the Series I and II L67 (all supercharged models 92-99) Including Olds 88's, Olds LSS's and Buick Lesabres Please use General Chat for non-mechanical issues, and Performance and Brainstorming for improvements.

Reply
 
 
 
Thread Tools Search this Thread
Old 02-22-2008, 03:19 PM   #1
Member
Posts like a V-Tak
Thread Starter
 
Join Date: Feb 2008
Location: INDIANAPOLIS, IN 46237
Posts: 38
Thanks: 0
Thanked 0 Times in 0 Posts
mustangman_93 is on a distinguished road
Default Suggestions on how to improve fuel mileage?

Hey guys, any suggestions on how to improve fuel mileage. I just changed my plugs to Autolite coppers gapped at .060 and stock replacement wires. I just got about 260 miles out of a tank - 14.4 mpg. A little poor if you ask me. I do warm up the car for a few min. before driving. Mostly city with a slight amt. of interstate driving mixed in approx 30-50 miles. Thanks Bryan
mustangman_93 is offline   Reply With Quote
Old 02-22-2008, 03:25 PM   #2
Senior Member
Posts like a Camaro
 
Join Date: Nov 2007
Location: MN
Posts: 1,172
Thanks: 0
Thanked 0 Times in 0 Posts
Bonnevillan is on a distinguished road
Default

how old is the 02 sensor?
Bonnevillan is offline   Reply With Quote
Old 02-22-2008, 03:26 PM   #3
Senior Member
True Car Nut
 
Join Date: Jan 2005
Location: Montevideo, MN MWBF '05, '06, '07 WCBF '06 '07 survivor
Posts: 3,882
Thanks: 0
Thanked 0 Times in 0 Posts
sonoma_zr2 is on a distinguished road
Default

I would get you O2 sensor scanned, you must be running pig rich. Or you have a hole in the fuel line somewhere
sonoma_zr2 is offline   Reply With Quote
Old 02-22-2008, 03:34 PM   #4
Member
Posts like a V-Tak
Thread Starter
 
Join Date: Feb 2008
Location: INDIANAPOLIS, IN 46237
Posts: 38
Thanks: 0
Thanked 0 Times in 0 Posts
mustangman_93 is on a distinguished road
Default

I bought the car from my brother and he said he never has replaced anything on the car except for brakes and the water pump. Which O2 sensor would be bad - front or rear? How about coils not firing properly. No holes anywhere in the fuel lines
mustangman_93 is offline   Reply With Quote
Old 02-22-2008, 03:37 PM   #5
Member
Posts like a V-Tak
Thread Starter
 
Join Date: Feb 2008
Location: INDIANAPOLIS, IN 46237
Posts: 38
Thanks: 0
Thanked 0 Times in 0 Posts
mustangman_93 is on a distinguished road
Default

Bonnevillan Posted: Fri Feb 22, 2008 2:25 pm Post subject:

--------------------------------------------------------------------------------

how old is the 02 sensor


Wouldn't the O2 sensor throw a code if it was bad? Also, checked tire pressure and they were all between 33 and 36lbs.
mustangman_93 is offline   Reply With Quote
Old 02-22-2008, 03:42 PM   #6
Junior Member
Posts like a Ricer Type-R
 
Join Date: Aug 2002
Posts: 10
Thanks: 0
Thanked 0 Times in 0 Posts
willwren is on a distinguished road
Default

They rarely throw a code unless completely fried.

Most O2'* we've found are getting tired around 50-60k miles. If yours is that old, or you don't know, I suggest you change it if you are having a fuel mileage problem.

If you're not getting at least 28mpg on the freeway, and you know OD works and doesn't slip more than 15 or so RPM'*, you need to be doing something about it. If the plugs and wires are good, the O2 is a pretty safe bet.
willwren is offline   Reply With Quote
Old 02-22-2008, 03:42 PM   #7
Senior Member
Posts like a Camaro
 
Join Date: Nov 2007
Location: MN
Posts: 1,172
Thanks: 0
Thanked 0 Times in 0 Posts
Bonnevillan is on a distinguished road
Default

EDIT: posted at the same time

no, they have to be almost completely gone to throw a code. Get a new one, just not Bosch.
the front 02 is the only one that actually does anything. the rear just monitors the efficiency of the front.
Bonnevillan is offline   Reply With Quote
Old 02-22-2008, 03:54 PM   #8
Member
Posts like a V-Tak
Thread Starter
 
Join Date: Feb 2008
Location: INDIANAPOLIS, IN 46237
Posts: 38
Thanks: 0
Thanked 0 Times in 0 Posts
mustangman_93 is on a distinguished road
Default

Will do today. Any other suggestions? Thanks
mustangman_93 is offline   Reply With Quote
Old 02-22-2008, 03:55 PM   #9
Member
Posts like a V-Tak
Thread Starter
 
Join Date: Feb 2008
Location: INDIANAPOLIS, IN 46237
Posts: 38
Thanks: 0
Thanked 0 Times in 0 Posts
mustangman_93 is on a distinguished road
Default

OD works fantastic and it does not slip.
mustangman_93 is offline   Reply With Quote
Old 02-22-2008, 03:55 PM   #10
Senior Member
Posts like a Camaro
 
Join Date: Nov 2007
Location: MN
Posts: 1,172
Thanks: 0
Thanked 0 Times in 0 Posts
Bonnevillan is on a distinguished road
Default

try the 02 first... if it doesn't fix the problem, i would look at the fuel filter
Bonnevillan is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Seven ways to improve the Winter Olympics MOS95B Lounge 1 02-24-2006 12:44 PM
400 mile road trip in 93 Olds 88, can I improve gas mileage? dbtk2 1992-1999 15 08-20-2004 12:06 AM
What mods will improve my gas mileage? Jrios 2000-2005 29 01-08-2003 08:25 PM
What can I do to improve my gas mileage? Blk_Bonneville 1987-1991 10 08-25-2002 12:15 PM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 02:42 AM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.