Sidewinder's Fuel Economy Almost 3-Year Journey

[Sidewinder]

JOIN ME!
Note: Not trying to upstage the post below, or above, or wherever it is with the year-long mileage count. I actually didn’t know that post existed before writing this. The other post I would say is more detailed than mine in that he did write down what type of driving he did. Funny that we had similar idea…

Before I start, there are few things I want to cover:

Thing One:

“Are you MAD!? You tracked fuel economy for 3 years since you bought the car?”

Short, yes, I am very mad. There was a method to my madness though. Firstly, I track fuel economy mainly to detect problems with my vehicle; sudden changes may be a sign that something is wrong. Secondly, I thought it might be interesting to see what kind of mileage a car maintains throughout its lifecycle and if it is even close to what it was rated. Lastly, BECAUSE SHUT UP!


Thing Two:

“Won’t there be some, variance, anomalies or other issues that may mess with the results?”
Also in short yes. Specifically my car has a very special issue I’ve been troubleshooting for literally 2 years now as of January. To keep suspense going, I will describe this in detail at the end. The other issue is converting to different measurements for fuel economy, which may not be as accurate (though my results seem to discredit that thought). I’m also relying on accuracy of my trip computer, which may also be as mad as me. I tried my best to keep things accurate; any gas bills that would skew the results would not have mileage recorded (apparently I really screwed July 2012 because none of them were marked). Finally, this is results from almost 3 years of ownership since I bought the car, therefore I cannot recall WHY I got the mileage I did (i.e. city or highway or both) and can only rely on my awesome (I guess not-so) recording skills.

Thing Three:

“What type of mileage does this represent?”
Also a good question, man you guys are smart. This represents mostly city driving, though there are highway runs mixed in (presumably the higher fuel econ. numbers). Therefore I would call these Mostly City But Some Highway Fuel Economy Numbers or MCSHFN for short.

Thing Four:

“What are you driving!”
The car is a 2010 Pontiac G3, driven in the snowbelt in Ontario. So I will have a mix of winter and summer driving. Snow tires were purchased before the first winter season and are represented in all fuel economy numbers.

Specs:

1.6 Ecotec with Variable Valve Timing
5 Speed Manual Transmission
All Season Tires and Snow Tires
Cruise Control (Added Summer 2012)
Spark Plug Recall (Summer 2012)
Removed Intake Resonator


Canadian Fuel Economy Ratings (from the window sticker, yes I still have it, again MAD)

City – 38MPG, 7.5L/100
Highway – 50MPG, 5.7L/100

The Numbers:
Fuel economy is measured in IMPERIAL miles per gallon and liters per 100 kilometers, the two standards in Canada. I may go through later and covert to US MPG measurement. In case you do not know, for miles per gallon higher is better, for liters per 100 kilometers (from now on L/100) lower is better.

Average Per Year

This actually stayed very consistent as you will see, something that I was happy to see.

2010 – 32.90MPG, 8.63L/100

2011 – 32.54MPG, 8.83L/100

2012 – 32.83MPG, 8.74L/100

Best By Year

2010 – 35.63MPG, 7.93L/100
2011 – 39.62MPG, 7.13L/100
2012 – 40.09MPG, 7.05L/100

Worst By Year

2010 – 28.96MPG, 9.75L/100
2011 – 25.19MPG, 11.21L/100
2012 – 25.63MPG, 11.02L/100

Best Overall

May 2012 - 40.09MPG, 7.05L/100


Worst Overall

Jan 2011 – 25.19MPG, 11.21L/100 (Incidentally, Jan 2011 wasn’t good to me, as the top two WORST ratings come from this month).

Very IMPORTANT NOTE….you better read this!
For the last two years, I have been dealing with a compressor issue in my HVAC system that I think may be the cause of some of my low fuel economy numbers. Granted I am theorizing but I will explain the issue for you to decide. There has been a slow leak for some time in my AC system, which started to cause noticeable rattling around Jan 2011 when the compressor was used.


This means that whenever the compressor is on it is dealing constantly with low pressure in the system. I think this may have caused strain on the engine, therefore affecting the fuel economy. The summer of 2011 (while I was trying to figure this out) I rarely used the AC system and instead used windows in fear that I may damage something (keeping in mind at this point I still did not know the cause as it was being diagnosed).


Jump to Jan 2012, when they finally decide to replace the blower motor and I get terrible fuel economy again as I am using defrost consistently. Jump to June 2012 (pretty hot one too) and using AC, fuel economy dives again. This is the time the pressure in the system is finally noticed and refilled (by a different dealership) and fuel economy numbers jump back up. It is still hot and AC is being used, but I saw a 7 to 10 MPG jump at the time that it was refilled.

Come December 2012 and the sound has returned. Dye is finally put into the system now that it is positive that it is a slow leak (which I still need to wait to find) and the system refilled for the second time.
Which leads me to this, the fuel economy (just a few numbers) from when I heavily used the compressor, mainly on hot days or in the winter:


Fuel Econ Jan 2011

25.32 MPG, 25.19MPG
Fuel Econ Jan 2012
27.97 MPG, 27.86 MPG
Fuel Econ June 2012
28.2 MPG, 25.63 MPG

After the system was filled:
Aug 2012 – 38.42MPG, 7.35L/100KM
First mileage count Jan 2013 after December refill – 33MPG, 8.53L/100KM

…and I have been using my defrost pretty much all the time (to cycle the refrigerant so the leak can be found. Once this issue is fixed, it will be interesting to see what my fuel economy is like.

Aside from my own interest, hopefully this can be a real world example of the 1.6 VVT gas mileage, including an example of what can happen if there are issues. I am happy with how consistent my numbers have been for the most part. Overall this car has been fairly efficient and has certainly saved me money in gas over my previous vehicle.

Over the next 4 months I will see how well it does doing mostly highway. Thanks for reading, any questions let me know.

[Pickles]

You had to get youre blower motor replaced? I did as well, and from what I have been reading it is semi-common with the 2010's. Im thinking there shouldve been a recall or something on them. I dont have A/C though, mine just stopped working all at once, as soon as winter hit

[Sidewinder]

You had to get youre blower motor replaced? I did as well, and from what I have been reading it is semi-common with the 2010's. Im thinking there shouldve been a recall or something on them. I dont have A/C though, mine just stopped working all at once, as soon as winter hit

It wasn't the blower motor though, they just replaced it thinking that was causing the noise and it wasn't. The AC system was low, so the condenser was having trouble keeping pressure, the low pressure caused the rattling noise I have been hearing. However, that could be why they thought that.