I have had my HCH CVT for exactly 2 weeks now. The low tank warning came on so I headed for the gas station. Here are the stats if anyone is interested.

I drove 492 miles. It took 11.9 gallons to fill up. That gives me 41.3 mpg.

When I picked up the car, the dealer had filled the tank. I set trip A as soon as I fired it up the first time. At fill up, that display showed 42.7 mpg. Just for fun, I set trip A after I had driven around for 200 miles and started to get an idea about how to drive more efficiently. That display showed 46.9 mpg over roughly 300 miles.

I am curious about the discrepency between the Trip A MPG reading and my calculated MPG. Is it typical for the calculated MPG to be less than the display?

Also I noticed that the low fuel light comes on when you reach one bar. This went on and off for a day, witht he fuel display showing one to 3 bars. Anyone know how to tell how low you really are form the display, or do you just go by mileage. It seems if you average 40 mpg with a 14 gallon tank, you should be able to go at least 560 miles before fill up. Can you really run the tank that low?

Your input is appreciated.

Clay

 

I am curious about the discrepency between the Trip A MPG reading and my calculated MPG. Is it typical for the calculated MPG to be less than the display?

Heck yeah, after calculating my mpg and comparing to my display I found the car was over 10% happy at predicting my mpg. It's not always that bad, but expect your calculated to be lower than your cars prediction.

Also I noticed that the low fuel light comes on when you reach one bar. This went on and off for a day, witht he fuel display showing one to 3 bars. Anyone know how to tell how low you really are form the display, or do you just go by mileage. It seems if you average 40 mpg with a 14 gallon tank, you should be able to go at least 560 miles before fill up. Can you really run the tank that low?

I think ther eis a thread about this somewhere. We all have had a similar experience. On my last tank, I figured I had one gallon of gas once the bars stopped moving up and down and the fuel tank light stayed on. Remember the tank only holds 13.2 gallons, unless you live in CA. Then it's even smaller. I like to fill up with about a gallon left, some here have said you can do some damage to your car if you let it run down to almost empty everytime. If you're getting a calculated 40mpg, I would fill up around 500 miles. You should be safe. I would also expect for your mpg to go up more. Good luck.

 

I think that most folks seem to notice a discrepancy of between 1 and 3 MPG. It seems to vary amongst drivers here, and a while ago there was an attempt to determine if the variance was specific to certain years of production (2003 vs 2004 vs 2005), or HCH type (ULEV vs AT-PZEV). I don't think we came to any conclusions.

My own personal experience is that 95% of the time, the difference is less than 1 mpg, and often less than 0.5 mpg.

What I think we would all say for certain, however, is that in order to get a reliable reading manually from the pump, you need to:

- always fill up to the same amount (e.g. the first pump auto shut-off), to eliminate top-off variances
- always fill up from the same pump at the same gas station, to eliminate pump variances
- wait for a few tankfulls and get an average, because single tank readings can be misleading due to variances stated above

I also don't think we have ever determined exactly *why* the results from the computer on the car are "optimistic". Speculation there varies from:

- Evil and biased car manufacturers (in this case Honda)
- Evil gas stations and pumps
- Evil oil companies (they don't really have anything to do with it, but it's still fun to blame them)

Sounds like you are getting good mileage, and it will improve over time. So congratulations on your hybrid, and enjoy your new ride!

 

If we do cut off after the first click when filling up, does that mean we have 13.2 gallons to use OR we can only get 13.2 when topping off?

 

I'm not sure I understand the intent of your question, but the reason I stated that you should stop when you get to the first click is purely for consistency's sake -- so that you have a standard for what "full" means, and therefore so that your calculations are closer to precise over time.

 

I'm asking do we have 13.2 gallons in the tank after the first click or is some lesser amount? Is the tank when topped off larger than 13.2 gallon capacity?

 

Hi Coyote:

___A first click’s gallonage dispensed can differ dramatically depending on the pump shutoff sensitivity, actual pump flow rate from one station to the next, and even flow rate from pump to pump at the same station! A top off cannot unless it is an unusual vapor recovery cap as can sometimes be achieved when refueling an Insight. You are far more consistent with the latter then the former in most vehicles in my experience with little variance no matter any of the variables above.

___BigBear, more.

___Good Luck

___Wayne R. Gerdes
___Waynegerdes@earthlink.net

 

Like 14 gallons or something like that?

 

That's correct, which is why I earlier mentioned that you should

"- always fill up from the same pump at the same gas station, to eliminate pump variances"

Either way you do it, topping off or not, changing stations and pumps or not, it should eventually average out over time, and what we are arguing about, with apologies to our mutual friend from Austin, is "littlebearballs". :-)

 

A'int no little around here, hehehe. No, jk. BBB is the first handle I ever used back in 1998. It's stuck with me and now I use it everywhere, even ebay. It's in homage to my alma mater, Baylor University. But you're right, I think all of us around here get a little obsessive about our mpg, including me. We should all be very happy to get 40+. When I was getting half that in my accord, I never seemed to care. You put that mpg gauge in front of me and I can't stop thinking about it.