No problems at all. As I was trying to indicate in the post above, I'm accustomed to relying on reading the signature so that I can tell the context for the reported problem or the reply.

I understand. I do think there's plenty of room.. but clearly that is not a priority in this forum. That's OK... it was just an observation.

 

OK... here's the results. The dealer says there's nothing wrong with my car. They checked the injector balance rates and they're in spec. They checked for dragging brakes and found no problems. So far... this is useful information.

So... the next step taken was to take the car over and fill it up, reset everything on the DIC and take the car for a drive. He drove 12.5 miles at 70 mph on the highway w/cruise control, then turned around and returned to the gas station. He put .6 gal of gas in it... and stopped checking anything else. I was unable to discuss anything else with him since the car, according to his test, gets better than 40 miles per gallon. I have no idea what DIC said.

Now that we have the car back, we're back to reading ~24.5 mpg on DIC, and this is still on regular gas. Next tank we're going to a) premium gas, and b) non-gasohol (gonna try to find gas without any ethanol in it)... and maybe a couple of other things.

Well... I know that a 25 mile distance is insufficient to truly test mileage... and unless you had a precise method of measurement for filling the tank, I doubt that you could get a precise identical fill level. But... for discussion purposes, let's assume that this is all cool. Maybe I bumped the reset button which caused our DIC setting to report for a part of the tank rather than the entire tank. That would explain a higher-than-reality DIC mpg. Maybe the hills were tougher on the car than I thought it would be, and that 22+ mpg at 70 mph is reasonable. Who knows?

We're going to try a few things to see if we can get the mileage up. Thanks for all of the suggestions on what to check, what to verify.

 

Randy,

I have been watching this thread for a while now because I too am interested in the gas mileage of my HHR. Until I had a DIC I didn’t know how much mileage can vary based on conditions. Oh, before I get too far, I have a 2007 2LT with a 2.4 and an automatic.

I live in Mankato, MN. Those of you familiar with Mankato know that it’s a hilly city with so many stoplights that you would think they are the area’s cash crop. According to the DIC I sometimes get as low as 15.9 MPG in the city. When I drive on the local rural highways at 55-60 MPH, however, I have gotten as high as 33.9 MPG (wind aided). Normally this local 55-60 MPH will yield about 27.9 to 29.9 MPG.

This past Monday I had to drive to Vermillion South Dakota and back in some pretty brutal conditions. The wind was gusting to 30 MPH and it was snowing and blowing pretty badly. On this trip I got 26.6 MPG according to the DIC. I didn’t think that was too bad given the conditions.

I guess I wouldn’t worry too much about the mileage I was getting so long as it appeared reasonable for the driving conditions. I also would not expect the same mileage someone would get with a 2008 Chevrolet Malibu with a 2.4 because the HHR just isn’t as aerodynamic as the Malibu.

So, I guess I really haven’t helped any but there are times when I’m not too concerned about the MPGs. I know that in my area there are times when they might be a bit low but when I need them to be higher, like on long trips, they seem to be high enough for me. I hope you can get the gas mileage thing with your HHR sorted out. I think they are neat cars!

PaulW

 

1st of all.
08 2LT 2.4 auto bone stock 1400 miles on it.
13.01 gallons at fill up w/premium fuel on this tank
200 miles on last tank
All city driving. No hills. No extreme accelerating. about 10 miles a day
36 psi average in each tire
DIC says 16 MPH average ( weird )
15.3 MPG

Filled again 13.18 gallons
DIC says 250 miles til empty

My DOHC V8 Maurader got the same mileage. This just plain sucks

 

The part I bolded is a big reason why your mileage stinks. You're driving short trips in-town. Your car isn't running at peak efficiency at all in those conditions. It might be a bit extreme mileage, but in very short trips, mine won't even get 20MPG. It just isn't efficient until it is fully warmed up.

 

This is the exact reason why I'm not complaining about my mileage. 90% city and most trips are less than 5 miles between stops.

BTW........my DIC mostly reads 20-22 mpg.

 

I let my car warm up every time I start in the morning. I wonder If I drive it harder will that help. I also am going to get the ECM reflashed when I hit 2000 miles.

 

Hey there, Just my .02
I've had my 07 HHR 2LT since last November, it has 2.4 auto, all options except 6 cd changer,, so I have roof racks, running boards, chrome package etc. I have just under 5000 miles. I have a commute that is on flat land in the central valley of Ca. which involves about 5 miles stop and go the rest is freeway. I commute from CHowchilla to Merced, for those of you who know the area, about 45 miles round trip. I used shell premium exclusively for the first 5 or 6 tanks. According to the display I can get over 30 miles per gallon if I'm driving say 65-68 mph, at around 70-72 it gets 27-28 mph. When all is said and done, I keep track of my mileage via the Trip A, and compute my mileage overall when I fill up, (using a calculator with a digital display,, ). I Usually fill up at about 1/4 tank. I have been averaging around 24 mpg overall using premium. I then switched and have been running the midgrade shell for the last few tankfulls, and my mileage dropped to 22-23 mpg overall. I am 53 and I have a drag racing background, so I let it wind up a bit,,, I love it,

 

Warming up the car wastes gas too. You're getting 0MPG with it sitting there idling. That will also kill your mileage, especially with short trips! Unless it's really cold (like <-10F) warming it up is unnecessary. Nice to have a toasty car mind you, but it does no good for the car or your gas mileage.

 

Ok to clarify, its only for about 2 minutes, enough to get the oil up from the pan. I am aware that short trips arent the best for MPG. But sweet Jesus, 15.3? Thats a far cry from 20. Some have said its not broken in yet however im not convinced of that.