why would my gas mileage drop - Chevy HHR Network
Chevy HHR Network Forums
Search

Go Back   Chevy HHR Network > Specific Technical Discussion > Fuel Economy - Hypermiling

Fuel Economy - Hypermiling Dedicated to discussions on fuel economy improvements and related modifications.

Reply
 
 
 
 
LinkBack Thread Tools Search this Thread
Old 01-02-2011, 11:12 AM   #1
Senior Member
 
Join Date: 06-14-2010
Location: tyler, tx
Member #: 21442
Posts: 102
Check out my gallery 
why would my gas mileage drop

I have been getting a consistant 28-32 mpg over the past 6 months and now I am lucky to get 25 usually 23-24. I keep my tires aired up, proper oil changes and other things along those lines. Why would I drop so badly? Same commute, same driving style if not better than normal. NO check engine lights.
TXhhr83 is offline   Reply With Quote
Old 01-02-2011, 11:49 AM   #2
Senior Member
 
Join Date: 09-11-2007
Location: Palm Bay, Florida
Member #: 4311
Posts: 1,367
Images: 18
Check out my gallery 
10% ethanol or 15% ethanol.. How many miles on the car? Tune up time? Winter weather, longer idle to warm up the car? Gas station pumps not calibrated short changed you in gallons pumped.
Old Lar is offline   Reply With Quote
Old 01-02-2011, 11:53 AM   #3
Senior Member
 
Join Date: 06-14-2010
Location: tyler, tx
Member #: 21442
Posts: 102
Check out my gallery 
up to 10% ethanol almost always use the same gas station since the gas light comes on at the same place every week. I just rolled 72k on an 07. I dont let it idle long before getting in it to drive, no more than I do when it is warm. I bought it used so I dont have any idea how the maintence log was before I got it. Its got me stumped. I probably need to replace the struts and shocks on it but I cant see that changing the mileage that much.
TXhhr83 is offline   Reply With Quote
Old 01-02-2011, 12:00 PM   #4
Senior Member
 
Join Date: 02-15-2008
Location: Stockwell, Indiana (Lafayette Area)
Member #: 5666
Posts: 370
Images: 42
Check out my gallery 
What brand of gas (BP, Exxon, Shell, etc.)? Ethanol content varies in each shipment of gas. Maybe your gas station has already implemented the 15% Ethanol and not changed their product signage.
__________________
T.T.F.N. - Tigger
Early 2007 LS - 5-Speed
Mods: Color Matched Running Boards, Custom Fit HHR Splash Gaurds, Dark Tinted Front Windows and Front Eyebrow, Custom MOMO 5-Spoke Rims with Dunlop Signature Tires, AirAid Intake Tube and Filter, Hidden Trailer Hitch, and TTR Rear Sway Bar

TiggersHHR is offline   Reply With Quote
Old 01-02-2011, 12:03 PM   #5
Senior Member
 
Join Date: 06-14-2010
Location: tyler, tx
Member #: 21442
Posts: 102
Check out my gallery 
usually shell or exxon depending on what side of the road the light comes on at.
TXhhr83 is offline   Reply With Quote
Old 01-02-2011, 02:49 PM   #6
Administrator
 
843de's Avatar
 
Join Date: 06-30-2010
Location: Kannapolis NC
Member #: 21740
Posts: 24,955
Images: 98
Check out my gallery 
I'd check the usual culprits like tire pressures, the air filter, whether the gasoline has been reformulated for winter, and for a curve ball even the alignment.
__________________
We won it, we won it, we won it!!! RDE 2/15/98

"Steam engines don't answer back. You can belt them with a hammer and they say nowt." - Fred Dibnah MBE (April 28, 1938- November 6, 2004)
843de is offline   Reply With Quote
Old 01-02-2011, 02:52 PM   #7
Senior Member
 
Join Date: 02-16-2009
Location: Frankenmuth/Flint, MI
Member #: 14016
Posts: 6,129
Images: 325
Check out my gallery 
I would think it would be a gradual decrease in mileage, but what about carbon build up?
__________________
2006 HHR 1LT, 2.2L, Auto, Running Boards, Roof Rails, Sunroof, Chrome Package (54k miles) Built 5/24/06, Purchased 2/17/09
Mods: Molded Splash Guards, Chrome Exhaust Tip, Brake Light Cover, Stubby Antenna, Gutter Guard Grille, Chrome Tail Light Rings, TTR Sway Bar, 2LT Wheels
1999 Chevy Lumina (164k miles) Built 9/9/98, Purchased 8/14/06
1983 Chevy C-10 Scottsdale Pickup (166k miles) Built 4/83 in Flint, MI, Received 1/05
urbexHHR is offline   Reply With Quote
Old 01-02-2011, 02:58 PM   #8
Administrator
 
843de's Avatar
 
Join Date: 06-30-2010
Location: Kannapolis NC
Member #: 21740
Posts: 24,955
Images: 98
Check out my gallery 
Probably not CCK, these engines run so close to the ideal 14.7 to 1 air fuel ratio I doubt they can really carbon themselves up. Back in the good old days engines did carbon themselves up since you invariably ran rich at certain engine speeds, like puttering around town. We still say we're "going to blow the carbon out", but in reality all we're probably doing is blasting some deposits off the plugs.
__________________
We won it, we won it, we won it!!! RDE 2/15/98

"Steam engines don't answer back. You can belt them with a hammer and they say nowt." - Fred Dibnah MBE (April 28, 1938- November 6, 2004)
843de is offline   Reply With Quote
Old 01-02-2011, 03:01 PM   #9
Administrator
 
843de's Avatar
 
Join Date: 06-30-2010
Location: Kannapolis NC
Member #: 21740
Posts: 24,955
Images: 98
Check out my gallery 
As another thought, TXhhr83 mentioned in another post about possibly trading his HHR in. Sometimes the act of falling out of love with a vehicle can cause your mileage to drop as you subconsciously "hammer" it for the lack of a better analogy.
__________________
We won it, we won it, we won it!!! RDE 2/15/98

"Steam engines don't answer back. You can belt them with a hammer and they say nowt." - Fred Dibnah MBE (April 28, 1938- November 6, 2004)
843de is offline   Reply With Quote
Old 01-02-2011, 03:03 PM   #10
Senior Member
 
Join Date: 08-10-2010
Location: Canton, OH
Member #: 22554
Posts: 104
Images: 3
Check out my gallery 
Possible muffler baffle came loose and is restricting exhaust flow.
__________________

Ken
2011 HHR - 2LT - AT - Sunroof - Victory Red - Gray Leather - Progress rear sway bar - Huskyliner front floor mats

Purchase date: 08 NOV 2011 w/9,689 miles
farmer52 is offline   Reply With Quote
 
 
 
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
Drop or no drop? Feedback needed plz eaglefreak138 Brakes | Suspension | Shocks | Struts 12 10-09-2011 03:18 PM
Does anybody else's mpg drop when it gets cold? Jim's 2009 Fuel Economy - Hypermiling 21 12-24-2009 07:49 PM
Can I drop a 2.4 in my Panel LS Panel08 General HHR 5 04-16-2009 06:43 PM
hey guys i want to drop my hhr? longislandhhr09 Brakes | Suspension | Shocks | Struts 1 03-19-2009 05:18 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 On
Pingbacks are On
Refbacks are On



vBulletin copyright ©2000 - 2015, Jelsoft Enterprises Ltd. Vb Style © vb-skins.com

Advertising - Privacy Statement - Terms of Service - Cookies - Jobs

Copyright © 2005 - 2013 Internet Brands, Inc. All rights reserved.
All times are GMT -5. The time now is 03:51 AM.
Chevy HHR Network Forums