Results 1 to 10 of 10

Bad Gas Mileage

This is a discussion on Bad Gas Mileage within the General Help forums, part of the LSx Technical Help Section category; This year my 2000 Z28, only has 42,000 miles, has been getting 11-12 mpg. Easy city driving, no flooring it, ...

  1. #1
    Junior Member
    Join Date
    May 2006
    Location
    erie
    Posts
    8

    Bad Gas Mileage

    This year my 2000 Z28, only has 42,000 miles, has been getting 11-12 mpg. Easy city driving, no flooring it, lol. I'm thinking it's time to replace the O2 sensors? Is it possible they are bad even with no SES lights? Car runs fine. What brand does everyone recommend, AC Delco? TIA!

  2. #2
    Senior Member tatertot91's Avatar
    Join Date
    Oct 2008
    Location
    Coral Springs, Fl
    Posts
    5,773

    Sunset Orange Metalic
    2001 Camaro SS

    When is the last time you did a full tune up? New plugs, wires, fuel filter, air filter, I would start there. New O2s probably wouldn't be a bad idea either. What octane of fuel have you been running?

  3. #3
    Super Moderator
    pajeff02's Avatar
    Join Date
    Feb 2009
    Location
    Mansfield, PA
    Posts
    21,576

    Black & Blue
    '02 WS.6 / '07 Suburban

    ^^ This. May as well clean the MAF while you are at it. I generally recommend Bosch P/N 13111 O2 senders, especially is you have headers as they have a longer harness.

  4. #4
    Senior Member tatertot91's Avatar
    Join Date
    Oct 2008
    Location
    Coral Springs, Fl
    Posts
    5,773

    Sunset Orange Metalic
    2001 Camaro SS

    My personal experience has me using denso sensors. Nothing wrong with bosch, I've just noticed that denso o2s read/switch faster. Also when I can its a plus going with the oem brand, especially for sensors imo.

  5. #5
    Super Moderator
    pajeff02's Avatar
    Join Date
    Feb 2009
    Location
    Mansfield, PA
    Posts
    21,576

    Black & Blue
    '02 WS.6 / '07 Suburban

    No actual testing to base this on, but my understanding is that the P/N 13111 sensors are faster switching than the P/N 13444. The latter being the Bosch stock replacement sensor for our cars.

  6. #6
    Senior Member JayTA98's Avatar
    Join Date
    Dec 2007
    Location
    Orlando, FL
    Posts
    3,351

    Mean Black
    1998 Trans Am

    I was having bad fuel mileage and I switch my O2 sensors to brand new Boschs. I don't have headers. I did noticed a change in my fuel mileage right away. My car had 110K when I swap them. Also make sure you don't use lower octane fuel it will drink it like ice tea in a hot summer.

  7. #7
    Smiles for 9.5 Years cammed goat's Avatar
    Join Date
    Jan 2009
    Location
    Paterson/Ridgewood, NJ
    Posts
    11,474

    Phantom Black Metallic
    2004 GTO M6

    Agree with all stated above.

  8. #8
    Senior Member theorangeguy's Avatar
    Join Date
    May 2013
    Location
    Nashville, TN
    Posts
    1,434

    Black / White
    '00 T/A M6/'15 Hemi Truck

    I've had a few things ruin my mpg in my cars...bad o2's and vacuum leaks are the ones I ran into the most though.
    2000 Black TA M6 - LT's, ORY, UMI Short Stick, TT2's, Drilled/Slotted Rotors, Braided Lines, and Tuned by Vengeance SCCA and Car Show Approved
    2015 Ram 1500 Crew Cab Sport Premium Hemi
    2010 Hemi Crew Cab Sport Premium - Tuner and HID's - Sold
    06 Quad Cab HHHHemi - Sold
    99 Hugger Orange Camaro - Sold
    97 Camaro - Sold

  9. #9
    Veteran 0rion's Avatar
    Join Date
    Aug 2005
    Location
    ohio
    Posts
    22,520

    98 Formula
    06 duramax

    any mods? Is the car running funny at all? I know you have a '00 which doesn't really have a functioning coolant gauge but is it at least moving up the scale like it should? I would start with maintenance items before just throwing O2 sensors at it. 42k miles isn't a bunch of miles to have on those sensors. That's not to say they still might not be bad because regardless of the mileage they're 13 years old. I would still start with cleaning the MAF, plugs/wires, ect ect since those are normal maintenance items that should be done anyhow.

  10. #10
    Smiles for 9.5 Years cammed goat's Avatar
    Join Date
    Jan 2009
    Location
    Paterson/Ridgewood, NJ
    Posts
    11,474

    Phantom Black Metallic
    2004 GTO M6

    Plug wires could be degrading given their age and being exposed to heat/cold. Is the car a daily driver? But I agree with cleaning the MAF. Give it a good spray and let it dry completely then reinstall. Do this first then get back to us if there is no change.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Gas Mileage
    By VOODOOII in forum External Engine
    Replies: 27
    Last Post: 08-24-2009, 09:10 AM
  2. Mileage
    By JwMonE99 in forum LT1
    Replies: 32
    Last Post: 01-27-2008, 06:06 AM
  3. LS1 Gas Mileage
    By LS1Powerhouse in forum Firebird / WS6
    Replies: 39
    Last Post: 06-29-2007, 07:14 PM
  4. bad gas mileage ls1
    By waylonSS in forum General Help
    Replies: 16
    Last Post: 09-23-2006, 05:10 PM
  5. 3.73 gas mileage?
    By jakef777 in forum Drivetrain
    Replies: 1
    Last Post: 09-11-2006, 02:07 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •