What part of the country are you in Debb? A 12 mile per gallon drop in the winter is right in line with what I experience depending on where your starting point is. On my old commute, I went from 55mpg to 45mpg in the winter, and my new (shorter) commute is even worse. When it's cold, the auto stop won't work until the car has warmed up fully--usually 10-15 miles of driving. That's a big component of the poor winter mileage, but it also takes more work to move cold parts because the lubricants thicken. Now if you're somewhere warm like Florida or Arizona, it's probably not winter driving...

What year is your car? If you have an '09, you already have the latest version of the software, and the update that we've been discussing isn't applicable for your car. What did the dealership say about your car?

 

The service manager is telling me my drop in gas mileage of 12 miles per gallon has to do with winter driving! Yeah, right. My IMA warning light went on yesterday after two months of the mileage dropping substantially.

The service manager is right. Expect a hit in fuel economy in winter. They fail to tell you that when you buy the car. If your lucky enough to be going through a cold snap like I am right now (-36C or -31F) also expect to get no (zero) heat from your car. The civic hybrid is really a poor car in winter.

 

Kinda makes you look forward to springtime! Hybrids make spring weather twice-as-nice!

 

That is very cold! We complain here in New Zealand if the temperature reaches 0 degrees F. I wonder how the Prius performs in extreme cold temperatures?.

 

That is very cold! We complain here in New Zealand if the temperature reaches 0 degrees F. I wonder how the Prius performs in extreme cold temperatures?.

From discussions with Pruis owners extreme cold is not a problem. But until I drive one personally when its this cold I cannot confirm this. Although the majority of taxi cabs around here are Prius.

 

I just dropped my car off at the dealer this morning due to IMA light.
It seems like everything works fine on mine when I drive.
Auto stop still works. When I go up the the hill the IMA bar goes up and I can hear the
engine. It only happens two days ago so I don't know if that effect my mileage or not.
I'm definitley getting less mileage but I think it's due to the cold weather since I live in the East coast.
I really hope it won't come back on again when I get it back.

 

That sounds about right for me too.
I don't know if this is a good practice.
When I know that I'm gonna stop I usually shut off the heater
so the auto stop will engage, then turn it back on once I accelerated.

 

Just got my car back and here's what it said on what they found and fixed.

" Found IMA code POA7F battery module deteriation. Update PGM and IMA software per bulletin 09-025"

I only own this car for only 7 months and the battery is already deteriorating?
I can see if it 5 years from now.
Well, I only finance it for 3 years. Will see if I will keep it longer once it's paid off.

 

Hi All,

My experience...I too have a 2009 Civic, approximately 7 months old with 3400 miles on it. I live in Minnesota, and we've had temperatures ranging from ~25 to ~-10 degrees F over the last 3 weeks. I recently noticed that my gas mileage was starting to fall off dramatically. Then 2 weeks ago, my Check Engine and IMA lights came on. Prior to the drop in mileage, and the warning lights, I was getting around 37 mpg (city driving). When I brought the car into the dealer, I was getting 28.5 mpg. The dealer did the diagnostic and found the same problem/solution as ADbntly lists. I asked him if the software update would improve the mpg. I was told to watch it. A week later, I'm now getting 25.1 mpg, "engine stop" never happens and the Vehicle Stability system reacts as the slightest provocation (with a loud groaning/motor running sound). Since it's gotten colder here, I've also noticed that it takes a lot longer time (compared to my 2006 Accord) for me to get heat.

Mark

 

My experience...I too have a 2009 Civic, approximately 7 months old with 3400 miles on it. I live in Minnesota, and we've had temperatures ranging from ~25 to ~-10 degrees F over the last 3 weeks.

What you can try is blocking off the front grill. My '07 allows foam pipe wrap to be stuffed in to completely block off the grill. The heat is far from satisfactory but it will help a bit.