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In February, a few weeks after owning my Cruze and with approximately 1300 miles on the odometer, I drove a 60 mile stretch of highway in the wee hours of the morning to see what kind of fuel economy I could get by driving as efficiently as I knew how. I was able to achieve a best average of 46.6 MPG over 25 miles/43.9 MPG over 50 miles. Until today, I had not been able to break past those numbers.
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At 14786 miles, I figured my average lifetime MPG was 34.96 MPG
14786 miles using 422.9 gallons (per DIC) = 34.96 MPG
Don't get me wrong, that's a great number, but I wanted more than that and I knew it was possible. So, over the next few days I started reading several different threads here at CruzeTalk suggesting different ways to squeeze MPG's out of the Cruze. Of all the different things I've read, I decided to try 3 things:
1: Start running 93 octane instead of the 85 that I've been running since I've owned the car in late January.
2: Increase tire pressure to 45 PSI cold
3: Set the spark plug gap to .035 on all four plugs
Everything thing else is just like it was from the factory.
I left the house to drop my daughter off at school, and decided that since I didn't have to work and there were no chores on the honey-do list, I would take the Cruze out for a bit to stretch her legs for approximately 100 miles and see what I could get out of her. I reset my EIC as my daughter was getting out of the car at school, then drove to McComb, MS for no reason other than to cruise around and test her performance after the modifications.
I decided to stay off the interstate and drive the major 55 MPH highway due to traffic. I passed through several small towns that slowly dropped speeds to 25 MPH, but with very few traffic lights. I also started the drive with no A/C and windows up, using only the vent to bring in cool air from outside as the temp was reading 72 degrees.
I stopped at a gas station after 51.4 miles and decided to grab a Coke and turn around to head back home. I had averaged 46.2 MPG for the trip and had BLOWN AWAY my 50 mile best average of 43.9MPG with a whopping 46.0 MPG. (I was so excited at that fact, that I forgot to snap a photo of what my 25 mile average was. Surely it was higher as well.)
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On the trip back, I turned on the A/C. Temps had already risen to 85 and I was starting to bake in the driver's seat. I intended to run the full route without it, but comfort finally won over test results. As I drove, I noticed my average MPG's steadily climbing across the board, and reaching numbers that I had only dreamed of before. Here are the final results, taken while sitting my driveway.
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Here are the numbers:
BEFORE:
Total MPG: 34.96
Best average MPG per/25 miles: 46.6
Best average MPG per/50 miles: 43.9
AFTER:
Total MPG: 46.2
Best average MPG per/25 miles: 50
Best average MPG per/50 miles: 48.7
Estimated 31.1% MPG overall gain
I attribute these gains simply to the modifications. All in all, I really didn't change much in the way of driving habits other than watching how quickly I accelerated. The ride is a little more hard from the extra tire pressure, but in all actuality I was probably running under-inflated at the factory specs of 32 PSI. The car has a lot more zip in it, seems to idle better, and reacts like a dream. I only THOUGHT that my Cruze was fun to drive before!!
I'm going to be paying more attention to myself as I log more miles, to see where I can really change behavior to get more gains.
A HUGE THANKS TO EVERYONE HERE FOR ALL OF THE VALUABLE INFORMATION. I COULDN'T HAVE DONE THIS WITHOUT YOU!!
At 14786 miles, I figured my average lifetime MPG was 34.96 MPG
14786 miles using 422.9 gallons (per DIC) = 34.96 MPG
Don't get me wrong, that's a great number, but I wanted more than that and I knew it was possible. So, over the next few days I started reading several different threads here at CruzeTalk suggesting different ways to squeeze MPG's out of the Cruze. Of all the different things I've read, I decided to try 3 things:
1: Start running 93 octane instead of the 85 that I've been running since I've owned the car in late January.
2: Increase tire pressure to 45 PSI cold
3: Set the spark plug gap to .035 on all four plugs
Everything thing else is just like it was from the factory.
I left the house to drop my daughter off at school, and decided that since I didn't have to work and there were no chores on the honey-do list, I would take the Cruze out for a bit to stretch her legs for approximately 100 miles and see what I could get out of her. I reset my EIC as my daughter was getting out of the car at school, then drove to McComb, MS for no reason other than to cruise around and test her performance after the modifications.
I decided to stay off the interstate and drive the major 55 MPH highway due to traffic. I passed through several small towns that slowly dropped speeds to 25 MPH, but with very few traffic lights. I also started the drive with no A/C and windows up, using only the vent to bring in cool air from outside as the temp was reading 72 degrees.
I stopped at a gas station after 51.4 miles and decided to grab a Coke and turn around to head back home. I had averaged 46.2 MPG for the trip and had BLOWN AWAY my 50 mile best average of 43.9MPG with a whopping 46.0 MPG. (I was so excited at that fact, that I forgot to snap a photo of what my 25 mile average was. Surely it was higher as well.)
On the trip back, I turned on the A/C. Temps had already risen to 85 and I was starting to bake in the driver's seat. I intended to run the full route without it, but comfort finally won over test results. As I drove, I noticed my average MPG's steadily climbing across the board, and reaching numbers that I had only dreamed of before. Here are the final results, taken while sitting my driveway.
Here are the numbers:
BEFORE:
Total MPG: 34.96
Best average MPG per/25 miles: 46.6
Best average MPG per/50 miles: 43.9
AFTER:
Total MPG: 46.2
Best average MPG per/25 miles: 50
Best average MPG per/50 miles: 48.7
Estimated 31.1% MPG overall gain
I attribute these gains simply to the modifications. All in all, I really didn't change much in the way of driving habits other than watching how quickly I accelerated. The ride is a little more hard from the extra tire pressure, but in all actuality I was probably running under-inflated at the factory specs of 32 PSI. The car has a lot more zip in it, seems to idle better, and reacts like a dream. I only THOUGHT that my Cruze was fun to drive before!!
I'm going to be paying more attention to myself as I log more miles, to see where I can really change behavior to get more gains.
A HUGE THANKS TO EVERYONE HERE FOR ALL OF THE VALUABLE INFORMATION. I COULDN'T HAVE DONE THIS WITHOUT YOU!!
