'11 LTZ RS Auto 6 MPG Log

[Crewz]

Just posting some results of the MPGs I'm getting in my new Cruze. I live in Houston, TX. My daily work commute is 13.8 miles (google mapped it). During rush hour it takes about 1 hour to get home. So there's lots of bumper to bumper driving. I would say my commute is normally 80% city 20% freeway.

City MPG is anywhere from 22 - 28 MPG. It depends on how heavy traffic is. On average my car reads 26 - 27 MPG city if I really keep the RPMs below 2K using manual mode. I found in manual mode I can get the car to go into 6th gear by the time I hit 35 MPH. Living in Houston, you have to drive aggressive at times or you'll get ran over which is when I'm seeing the lower end of 20 MPGs.

Freeway MPG has been anywhere from 30 - 35 MPG. On average I would say 32 MPG. This is cruising anywhere from 60 - 70 MPH. I've just recently really started keeping track of my MPGs on the freeway. Last night I had band practice and there was very little traffic on the freeway so I started to log my MPG. These are the results with about 30% of my travel hitting lights and the rest freeway. The trip was about 15 miles.

You can see the MPG rise over the coarse of the pictures. These pictures were taken minutes apart. The last few were as I was getting off of the freeway. I tried to keep a speed of about 60 MPH, but traffic was trying run me over (a semi). I did want to drive next to the guy.

[Crewz]

Also, in Manual mode, I found you can start out in second, or maybe it's just automatic from first to second but changes quickly(?), gear which can help a little with the city MPG.

[Crewz]

BTW, this is on cat pee gas, 87 octane.

Does anyone know whether filling up with 93 octane will allow the cars computer to advance timing getting better MPG, maybe even build a little more boost?

[Jim Frye]

BTW, this is on cat pee gas, 87 octane.

Does anyone know whether filling up with 93 octane will allow the cars computer to advance timing getting better MPG, maybe even build a little more boost?

It might help a bit, but I doubt that the mpg improvement will offset the cost of the 93 octane gas. You'll have to try at least a couple of tankfuls of 93 octane to see what the cost/benefit really is for your style and driving environment.

Jim

[Crewz]

It might help a bit, but I doubt that the mpg improvement will offset the cost of the 93 octane gas. You'll have to try at least a couple of tankfuls of 93 octane to see what the cost/benefit really is for your style and driving environment.

Jim

That's true. I was looking at it from a miles per tank vs cost. Something to consider though.

[alex725]

My mpg went up when I switched from Regular to Mid-Grade, but it only went up by 1.5 mpg. I was getting a solid 30MPG on my commute to work on regular gas, then I got to 31.5MPG on mid grade.

My new commute is now 31 Miles each way with 14 miles highway (doing 75-80), 5 miles of mostly stop and go, then 12 miles of back roads cruising at around 45-50 mph with a couple traffic lights thrown in.

[Crewz]

I filled up with 93 octane this weekend. I'll see if there's any improvement. So far it seems to be sipping the gas just a little more and it seems a touch peppier. It could just be in my head.

[Crewz]

I filled up with 93 octane on Saturday. My average MPG has been around 26 - 27. Average driving MPH has been around 25.5.

I noticed I was getting worse gas milage when I would put the car in manual mode and keep the rpm between 1 - 2K. That's cause I was bogging the engine making it work hard. It seems happiest between 2 - 3K.

Here's a pic of my MPG after resetting when I left work. My trip from work was 18.8 miles. A/C on the whole time. RPMs in the 2 - 3 K range and during heavy rush hour traffic. Average MPH is 25.

Not too bad. I can only image what my MPG was with my RAM 1500 sitting idle in rush hour.

Tonight will be some hwy driving cause I have an evening band practice. We'll see what it does – if it's getting better since last week after some break-in miles.

[Quazar]

^
I've been saying for a while, if you can coast along, the engine does fine at 1300 rpm, from what I can tell between 1250-1300 it get the best MPG. But this is in a coast situation one, where say you can used cruise control.

If its stop and go or very hilly, 1700 - 2300 is what I found is best.

[stocker2]

>> Crewz
Sounds like you got a commute down 290!

About the best use of RPM discussion: I've had a scanner hooked up to my eco and in 90+ degree weather you will run negative timing under 2500 rpm while at full throttle (negative spark timing means the engine is running quite inefficiently), so it seems best to use 2000-3000 rpm if a decient level of acceleration is needed.

At 1300 rpm you're in a good spot as long as you're on a flat road and not accelerating.