Chevy Cobalt Forum banner

961 - 969 of 969 Posts

·
Registered
Joined
·
12 Posts
I get 28-31 depending on the weather and my driving with my 07 LT 4 door 5spd. Also I am running snow tires at the moment. Hope to increase my fuel milage with better tires.
 

·
Say What again!
Joined
·
6,125 Posts
I get 28-31 depending on the weather and my driving with my 07 LT 4 door 5spd. Also I am running snow tires at the moment. Hope to increase my fuel milage with better tires.
What kind of driving do you do (in respect to city/highway percentage)? Yeah, snow tires usually kill a few MPG, especially when I put my Altimax Arctics on my Cavalier and my brother's Buick - though they made up for it in bad-assery in snow. Our Cruze diesel has Michelin Xi3s, which are also great in the snow - but are also LRR tires, so they lessen the hit to fuel economy quite a lot.

Downside is you pay about double - but they have a stiff sidewall and actually handle better than the stock LRR Fuel Max All seasons.
 

·
Registered
Joined
·
508 Posts
My 08 LS BC with cruise @ 117K mi is getting 34-38 mpg with ave speed of 67mph over 400mi run ....but I only use it to go down hill. :wink2:

Just did another run of 400 miles @75-+80 mph @34mpg. Then filled up and Drove 65 miles per hr for 50 miles @ 38mpg now @118k miles

So I guess its running fair
 

·
Registered
Joined
·
330 Posts
When i bought the car in april 2019 it showed only 17 mpg, which was believeable. At the time it would drink almost a whole tank in under a week. After I did an induction cleaning, NGK spark plugs, and raising the tire pressure to 35 psi, I now show an average of 27 mpgs most of the time. I drive 30-45 mph Monday through Friday just going back and forth to work. On the weekends the averaged usually rises due to traveling on the freeway most of the time. At best the car has done 36 mpg. At worst 24 mpg, but thats not too often unless I let it idle, such as warming it up on a cold day during the week. Idleing does waste fuel and lowers the average. So I try not to too often.

I do not however let the fuel drop below 1/4 tank. I have changed a lot of fuel pumps on customers cars over the years and realize its important not to let the fuel run low for a submersible fuel pump.

I do wish the automatic transmission would shift into 4th gear below 40 mph. I usually just get the car up to 40 and hit the cruise control and drop down to 36-38 mph when trying to stay around a 35 mph speed limit. It does affect mpgs if it stays in 3rd gear as ive experimented over the past 11 months of owning the car.
 

·
Say What again!
Joined
·
6,125 Posts
Sounds like your current fuel economy is right about in line with where it should be. And good work on not letting it drop below 1/4 tank - it's a great way to overheat and chew up a pump. The 3rd and 4th gen Camaro/Firebirds were notorious for doing that if you consistently ran them low. When I pulled the fuel filter on my '86 IROC (about a month before the pump got changed), the fuel that came out was silver.

And regarding the transmission, 40mph is the general point where most automatics will shift into OD, so it's pretty normal. For what it's worth, with the stock 195/60R15 tires, 4th gear at 40 mph is only 1371 rpm - that's a pretty bare minimum in RPM. 35 mph would be 1200rpm, and on something without a ton of low end torque (like, say, a V8), it gets hard to maintain speed in that gear if any corrections are necessary.
 

·
Registered
Joined
·
23 Posts
i just checked the computer yesterday and it read 14 MPG. not suprising when all i do is slam the throttle and drive in neighborhoods. Do fill up on that premium gas though.
 

·
Registered
Joined
·
2 Posts
I just cleaned the throttle body, so my idle is a bit high. I get about 27 in mixed driving. Before I cleaned the throttle body I was getting about 30 in mixed driving.
 

·
Registered
Joined
·
330 Posts
How high is the engine idling? That should have had the opposite affect on the mpg. Although extended idling, especially in winter, can cause mpgs to lower. For me it seems I won’t just start and go like it do in warmer months. Maybe out of habit I let the car warm up longer. I just know the mileage usually goes down more when it’s colder. Although it may be that warmer air actually causes better fuel mileage. Less power, but better mileage. I could swear that’s been discussed on this site in the past. I have no idea if that’s what’s happening to you’re car though.

In town if my average speed is below about 27 mph, my mileage will sit at about 24 mpg. If I have an average speed above 27 mph, the mpg is 26-27 mpg. Highway mileage is usually 34-36 mpg from 55-65 mph. If I am able to go 70-80 mph, the mpg is 29-32 mpg. And speed limits here in Texas are pretty high in a lot of spots. Average speed and idling affect mpg. So does temperature.

Currently I have done very little highway driving. Mostly to and from work. Around town, and through shopping centers. Lots of idling. So I’m not getting the best fuel mileage. I can’t complain though compared to the cars I used to drive that were both V8s.

I’m not even sure the average mpg on the display is correct. Sometimes it’ll be under. And other times it’ll over estimate. As far as when I’ve checked miles driven and amount of fuel used. So it could be falsely stating the mpgs you actually are getting.
 
961 - 969 of 969 Posts
Top