gas milage
Thread Starter
Burning Brakes
Joined: Aug 2010
Posts: 1,148
Likes: 22
From: Portland OR
gas milage
Anyone got any ideas on why I am only getting 18 miles to the gallon? 2001 covertible,auto,
stock except intake and exhaust.41 k running toyo proxies. 17x8.5 front and 18x9.5 rear.I am a light footed driver.
stock except intake and exhaust.41 k running toyo proxies. 17x8.5 front and 18x9.5 rear.I am a light footed driver.
Safety Car
Joined: Sep 2005
Posts: 4,062
Likes: 103
From: Southeast, Tennessee
St. Jude Donor '09 thru '26
check to see if your car has thrown any codes (that would be first thing to check). you definitely have something amiss. perhaps something as simple as a tune up and wire change (if it hasn't been done for a while). could be a lot of different things. does the transmission seem like it is slipping at all??
Race Director
Joined: Jul 2007
Posts: 18,681
Likes: 47
From: Reno is so close to Hell you can see Sparks , State Of Confusion
St. Jude Donor '12-'13-'14
18, Is that highway and city driving combined?
I get maybe 17 city. (Heavy Foot) on the road with cc on I get about 29mpg.
I get maybe 17 city. (Heavy Foot) on the road with cc on I get about 29mpg.
Le Mans Master
Joined: Sep 2010
Posts: 5,520
Likes: 5
From: Long Island NY
If you don't do much highway driving 18 MPG's sounds about right. I do mostly highway and get about 23-24, however this number goes south with a lot of stop & go. With only 41K your plugs and wires should be good. Check your tire pressure and get a new air filter if you havent changed it in a while and change your fuel filter too if you already havent. If the simple stuff checks out OK and your car is running good w/o any codes I wouldn't worry about it.
Race Director
Joined: Mar 2007
Posts: 16,154
Likes: 0
From: Kali
St. Jude Donor '11
Just wait for ppl telling you that you're supposed to get Mid 30s...
Lots of factors go into gas mileage, having an A4 gets you worse MPG than M6, and then it depends if you do a lot of in town driving.
I get about 15mpg in town and high 20s highway.
Lots of factors go into gas mileage, having an A4 gets you worse MPG than M6, and then it depends if you do a lot of in town driving.
I get about 15mpg in town and high 20s highway.
Race Director
Joined: Jul 2007
Posts: 18,681
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From: Reno is so close to Hell you can see Sparks , State Of Confusion
St. Jude Donor '12-'13-'14
Instructor
Joined: Dec 2010
Posts: 102
Likes: 0
From: Pensacola Florida
18 is not terribly bad. I have an 01 and about 90% of my driving is in the City (at Highway Speeds). I stay at between 19 mpg and 21.
Try resetting your Avg. MPG on the display at every new tank to get a more accurate reading.
Are you using premium fuel?
Try a bottle of Techron fuel additive.
Does your air filter need cleaning?
Is it time for an an oil change?
Are your tires properly inflated and balanced?
Don't forget to clean the modular spindulator by pulling the pull string behind the progressive fuel dialator.
Try resetting your Avg. MPG on the display at every new tank to get a more accurate reading.
Are you using premium fuel?
Try a bottle of Techron fuel additive.
Does your air filter need cleaning?
Is it time for an an oil change?
Are your tires properly inflated and balanced?
Don't forget to clean the modular spindulator by pulling the pull string behind the progressive fuel dialator.
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I agree that if that is in town driving, it's not unusual. If it is a combo or all highway, then yes, it does seem like a low number. Check all the usual things and it they are OK, might be time to get the car fully checked by a good mechanic.
Thread Starter
Burning Brakes
Joined: Aug 2010
Posts: 1,148
Likes: 22
From: Portland OR
Thank you for the response.To start with this is combined milage but on this tank 80% of a 100 miles are hiway.The oil is clean and was just changed about400 miles ago[Mobile One].Fuel is Chevron premium[always]Tires are all at 28 psi.K&N air intake filter is clean.The tranny is not slipping.I have been on trips where I was on the hiway most of the time and still did not get the milage that I should be getting.Two friends of mine get 25 to 32 mpg.These are codes that came up, AO-LDCM/A1 RDCM/BO-RFA show 3 codes for each and this one 10-PCM has 1 code.I don't know what they are or how to find out. I will appreciate any help.
Thank you
Fred
Thank you
Fred
Last edited by memmer; May 7, 2011 at 02:10 AM.
Racer
Joined: May 2007
Posts: 435
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From: Newcastle, UK
Racer
Joined: Feb 2010
Posts: 375
Likes: 0
From: South Carolina
Thank you for the response.To start with this is combined milage but on this tank 80% of a 100 miles are hiway.The oil is clean and was just changed about400 miles ago[Mobile One].Fuel is Chevron premium[always]Tires are all at 28 psi.K&N air intake filter is clean.The tranny is not slipping.I have been on trips where I was on the hiway most of the time and still did not get the milage that I should be getting.Two friends of mine get 25 to 32 mpg.These are codes that came up, AO-LDCM/A1 RDCM/BO-RFA show 3 codes for each and this one 10-PCM has 1 code.I don't know what they are or how to find out. I will appreciate any help.
Thank you
Fred
Thank you
Fred
Safety Car
Joined: Jun 2004
Posts: 4,986
Likes: 393
From: Stoney Creek Ontario
check the basic stuff - it's a 10 yr old car, not much mileage on it though, but it's getting old.... when's the last time it got new plugs/wires/air filter? time takes as much of a toll on those "consumable" parts as much as total mileage does! also, a couple of weak 02 sensors can cause a drop in mileage even without showing any codes.....my mileage started dropping a few years ago and replacing those items brought it back up to like new performance....
Le Mans Master
Joined: Sep 2007
Posts: 7,604
Likes: 8
From: Belleville Il
Just to cover all the basis,,I WOULD check your plugs!! I did mine at 55K,,and the original plugs had lost a lot of the little platinum "pucks" off of the ground strap,,making many of the gaps WAY too wide. The car seemed to run pretty well in that condition,,but new plugs and wires made a great improvement!!Now I'm not saying it's going to suddenly get you up to mid twenty's,,but it doesn't cost a lot,,and then you will know it is going to be doing it's best!!Now I do have an M6,,so it is a little easier to get good MPG,,WHEN I behave myself
!! Now it is amazing just how little romping really knocks the crap out of your mileage,,so that too may be a factor. It is just soo easy,,and fun to just give it a little romp here and then,,and there goes the average
!! Again,,check those plugs,,you will probably be surprised how out of wack they are!! 
!! Now it is amazing just how little romping really knocks the crap out of your mileage,,so that too may be a factor. It is just soo easy,,and fun to just give it a little romp here and then,,and there goes the average!! Again,,check those plugs,,you will probably be surprised how out of wack they are!!
Heel & Toe
Joined: May 2011
Posts: 17
Likes: 0
From: Carrollton Texas
You did not mention if you bought the car used or new. Could it be that you have the optional 3.15 rear axle ratio instead of the standard 2.73 ratio?
The RPO code codes are
GU2 for the 2.73
G90 for the 3.15
The list of build codes for my car are in the glove compartment.
Just a suggestion.
The RPO code codes are
GU2 for the 2.73
G90 for the 3.15
The list of build codes for my car are in the glove compartment.
Just a suggestion.