Thanks! Does Michelin affect mpgs any? Being that its not a low resistance tire. Just want to be sure I don't drop of mpgs too much.

 

Hi

I recently purchases a 2009 Hybrid and is concerned with the fuel mileage. It si almost twice the rated 21mpg combined. The dealer says that winter can cause that and that once there is no service hybrid system message - they cannot do anything. The warranty for the Hybrid system will also end soon. How do i ensure that the hybrid system really works? We have driven the vehicle for a month - almost daily - we see the Auto Stop sometimes, battery charging often and hybrid power sometimes. But what is strange is that in park - the engine is on instead of battery power.
Thanks

 

Once warmed up the engine should go to autostop in park, as well as at stop lights, bank lines, and driving thru at low speeds in the shopping malls.

 

Thanks

I am getting 10.69 MPG with me alone driving in winter. paved road - 2 wheel drive. City and Highway combined. Does this seem usual in winter?

 

No. The least you should get is 17mpg city and the most is 25mpg. Make sure you use premium and measure it from top fill up to top fill up.

 

Thanks

 

What is your usual commute distance per key cycle? Are you using remote start for warm ups? When outside temperatures drop below freezing, it can take a half hour or more steady driving to get into Auto-Stop

The colder it gets, the longer it will take to get Auto-Stop.

 

If your mileage is that bad, most likely you need to look past the hybrid part and at the engine/fuel injection/computer controls. You can have an O2 sensor reading off a bit, a bad or dirty plug plugs, leaking fuel injector, dragging brakes, front spindle bearing going bad, or other mechanical issues that the computer doesn't necessarily catch. They are supposed to but don't always, especially if the issue is at the edge of being ok.
Those things are not covered by the hybrid 100k warranty unfortunately, an to be honest not all dealers have mechanics that can fix things that are not listed in the troubleshooting list in the book. For example I had a new 03 Trailblazer with 6 cyl 2wd, rated 16 city 22 highway. It got 10.5 by dealers test, ran just ok, and the dealer could never fix the mileage. Traded for 04 Rainer with 5.3 v8, rated 16/22 and it got 16 city and 22 on highway. Go figure.
BTW: My 02 Tahoe 4x4 with 4:10 gears got better than that, averaging 12-13.

 

1/2 hour will be the usual 1 way trip but I did drove for about 1 hour one day and when I parked in the driveway - engine kept running instead of the battery taking over. I do see the Auto stop but very few times in the last month. I understand from evois that I should expect 17mpg - the worst - you think that by only driving 1/2 hour steady will give be below 11mpg? I stopped remote starting but did not see a big improvement. With the best driving, no remote start - 2 wheel drive - 11mpg. combined.
Another thing is that when I stop at lights or anywhere with the car still in drive, with the brake on - the instant fuel economy reads 99 on the DIC. Is this normal?

Thanks

 

Thanks 1T1 GMC
The Dic was reading something like "service emission system" and I had the co2 senor changed. I will have the brakes etc looked at.
I also checked physically by adding fuel and then checking how many miles I get before the next fill and it matches the dic consumption so either the engine is guzzling the gas, because of brake, plugs or other issues issues or the hybrid is not working.