[Deane850]

CTS gas milage

Hello, i've got a 2003 CTS, and lately it's been getting horrible gas MPG, basically 18-20ish. I've just got the oil changed AND replaced the gas filter again, and still no change... I've alway put premium gas, as required, and still nothing better. It used to get at least 25 MPG. Any ideas??

 

[RightTurn]

Re: CTS gas milage

Hello Deane and welcome. Check out this previous thread for more info http://www.cadillacforums.com/forum...im-getting-sick-my-mpg.html?highlight=mileage . Also, the forum search feature is your friend!

:welcome:

 

[Deane850]

Re: CTS gas milage

Thanks, i guess, it's not going to change i suppose i'll just get a Kia, LOL

 

[TAWoody]

Re: CTS gas milage

My average MPG is roughly 19, so NOW you're getting normal MPG. Also, I don't think that your CTS requries premium unless they changed that?? My 06 doesn't require anything above the lowest grade. But I put medium in it anyways.

 

[dynalub]

Re: CTS gas milage

Hi, I just arrived in Central Florida. My trip started in Penna. I adveraged 25.7 MPG. This made me very happy.I hope I get the same when I return. Tom

 

[dj-makinnoize]

Re: CTS gas milage

You may want to look at your driving habits. I've heard the ECU on our cars take about 100 miles to adjust to your particular style so, if you have been driving like a bat out of hell...you will probably get lower MPG for a while. My 03 owner's manual recommend's premium fuel. It says you can try the lower grade fuel but, if you get a knocking sound to go back to premium. I didn't believe there was actually a difference in the fuel but, sure enough I got a knocking sound. I think the newer CTS's recommend lower grade fuel.

 

[Deane850]

Re: CTS gas milage

Thanks for the info... And I don't drive like a bat outta hell thanks, lol. And yes, the 03 was the first year, and it does require premium fuel, I got the knocking too, and returned to premium, quite some time ago. That's why I don't understand why all of the sudden the mileage, is so bad. But thanks for the info, and I guess it's just gonna be that way...

 

[wait4me6920]

Re: CTS gas milage

Thanks for the info... And I don't drive like a bat outta hell thanks, lol. And yes, the 03 was the first year, and it does require premium fuel, I got the knocking too, and returned to premium, quite some time ago. That's why I don't understand why all of the sudden the mileage, is so bad. But thanks for the info, and I guess it's just gonna be that way...

If you've not changed the way you drive, one would think that there should be a reason for a fairly significant change in mileage.

Might be worth springing for a new air filter if you've not replaced it recently. Also check to ensure that your tire pressure hasn't dropped to the point where it may be a factor.

Of course, mileage will usually suffer a bit during winter months if you live in a wintery climate.

Are you throwing any codes that could indicate a leaking injector, whatever? http://www.cadillacforums.com/forums/cadillac-forum/t-46420.html

Good luck...

 

[View]

Re: CTS gas milage

For me, gas milage in a city = 19 - 20 MPG
out of town/highway = 25 - 28 MPG

BIG DIFFERENCES!!

 

[Deane850]

Re: CTS gas mileage

My brother has one of those machines to hook up to, to see if it's throwing any codes, that will be done this week... I did change the air filter as well a few weeks ago, that was my first thought... I think i have some fuel injector cleaner bottles in my garage, i think i'll throw them in the gas tank as well, i suppose that can't hurt anyway. Thanks!!!

 

[PauL IzzI]

Re: CTS gas milage

my 06 cts requires the lowest grade gas, the dealer made a point to me when i was purchasing my baby, that you should only put the lowest graded fuel, i was very suprised because going from a 93 honda accord to an 06 caddy, i thought i would definetly be a premium guy, to my suprise (and happiness) i dont have to.... THANKS GM!

 

[ILLMATIK]

Re: CTS gas milage

Its not your driving habits, the CTS gets really crappy mileage, but at least it runs on regular. I get about 10-12 in the city and 20-22 on regular 20-30 minute trips on the highway. Hopefully this SEVERE problem will be addressed in the next generation model coming out next year.

 

[RICADDYMAN]

Re: CTS gas milage

You need to feather your right foot more on the gas pedal, & maybe not be in "Sport Mode" all the time. I find that the combination of these two things vastly improved my mileage to the point of making me happy.

 

[LS1Mike]

Re: CTS gas milage

I have noticed the CTS does not get the best gas mileage in the world. My Trans Am with the 6 speed gets better MPG on the highway going 70.

 

[CTX-SLPR]

Re: CTS gas milage

I'd bet the Trans-Am has a better Cd and with the T56 has a taller final drive ratio as well. Not to mention that the LS1 is very efficient engine, a C6 Z06 gets 505hp without scratching the Gas Guzzler tax, I find that very impressive.

 

[schill32]

Re: CTS gas milage

What do you mean by a knocking noise? I have something similar in mine but it almost sounds like a lifter noise. Could this be the same thing? Oh, I've always used regular (cheap stuff) in mine. My other car is a supercharged Z24 Cavalier. So premium in one car is enough for me!

 

[Anyadike]

Re: CTS gas mileage

Yeah, high grade is recommended for the 2003, but isn't required... Here's a cut-n-paste from page 6-3 of the 2003 CTS owner's manual pdf on mygmlink.com...

"Use premium unleaded gasoline with a posted octane of
91 or higher for best performance. You may also use
middle grade or regular unleaded gasoline rated at 87
octane or higher, but your vehicle’s acceleration may be
slightly reduced. If the octane is less than 87, you may
get a heavy knocking noise when you drive. If it is bad
enough, it can damage your engine."


Also, the 2003 without Nav is one of the easiest to read codes-on if you want to try http://cadillacfaq.com/faq/answers/codes.html - The page includes the link for deciphering the codes....

My brother has one of those machines to hook up to, to see if it's throwing any codes, that will be done this week... I did change the air filter as well a few weeks ago, that was my first thought... I think i have some fuel injector cleaner bottles in my garage, i think i'll throw them in the gas tank as well, i suppose that can't hurt anyway. Thanks!!!

 

[Deane850]

Re: CTS gas mileage

Thanks for the info, i'll pass it on to my brother...

The 93 grade, truely runs better in the car...

I've also got the "lifter noise" that one of the replies states, i think it just the way it is, i don't think it's a problem...

 

[DDS rollin a CTS]

Re: CTS gas milage

Its not your driving habits, the CTS gets really crappy mileage, but at least it runs on regular. I get about 10-12 in the city and 20-22 on regular 20-30 minute trips on the highway. Hopefully this SEVERE problem will be addressed in the next generation model coming out next year.

ILLMATIC - I think you need to get your car in for service because I've never heard of anyone getting 10-12 MPG in their CTS.

Driving habits and "sport mode" definately play a role in your gas mileage. I used to keep my car in "sport mode" all the time and would average around 18-19mpg in the city. Recently I turned sport mode off and slowed down my driving a little bit and now I'm getting 20-21mpg in the city. On the highway cruising at 75-80 I average around 25mpg. I've seen as high as 30mpg average on a trip to West Virginia with an average speed of 60-65mph (county roads).

I always run premium gas and use Mobil1 oil (changed every 5000 miles). I've tried regular gas and though I didnt hear any knocking I could definately feel a difference in throttle response and accelleration.

 

[ILLMATIK]

Re: CTS gas milage

I took it to the dealer. Nothing's wrong with the car. The 10-12 mpg i get is in the city. I live in NYC and theirs a traffik light every couple of blocks. On the highway i get anywhere between 18-22 but to in all fairness my highway trips are very short 20-30 minutes tops. I've only been on the road longer than an hour on two or three occassions.