I've driven the car enough to get a feel for it. The instrument cluster has reliably reported 30-31 MPG and I can go 230 miles before it hits 1/4 tank. Last tank it reported 24 MPG and I was at 1/4 tank with 190 miles driven. That's a significant drop in fuel economy that I haven't experienced in similar conditions with other vehicles.
Hot weather killing fuel economy?
- Thread starter dishdude
- Start date
I've driven the car enough to get a feel for it. The instrument cluster has reliably reported 30-31 MPG and I can go 230 miles before it hits 1/4 tank. Last tank it reported 24 MPG and I was at 1/4 tank with 190 miles driven. That's a significant drop in fuel economy that I haven't experienced in similar conditions with other vehicles.
Then it’s most likely not just the hot weather, there’s something else going on since hotter weather should help.
Not to be a jerk here, but if you were getting a true 30mpg, your car should be getting around 280 miles on 3/4 of a tank, not 230 (12.4 gal x 30 mpg = 372 miles, x 75% used = 280). If you do a lot of city driving, I don’t think it would be too crazy to see any engine drop 20% off its city ratings, especially with A/C on and lots of stop and go.
If the indicated average doesn’t come up, take it to the dealer and have them check it. It’s under warranty for a long time at that mileage.
the image gives another detail, yet hides the most important one i'd say; your car sits in the individual mode, thats is to say the worst mode for gas efficiency, think it like pedal to the metal mode, yet the image does not display the level of the fuel in the tank
those thanks are more prone to ups and downs in MPG readings curve when full, while the curve has a tendency to even out towards when the tank is empty
those thanks are more prone to ups and downs in MPG readings curve when full, while the curve has a tendency to even out towards when the tank is empty
This. Especially with automatic climate control.
With automatic climate control, the AC runs more to maintain the set temperature.
I don’t trust the number on the dashboard. Hand calculate your MPGs so you know you’re comparing apples to apples.
Just my $0.02
Just my $0.02
As I calculated for the OP… his 230 miles to 1/4 tank does not line up with the indicated mpg and tank size. Losing 50 miles on 12.4 gallon tank is nearly 4mpg difference in indicated vs calculated!
This ^^^^^^^^^^^^
All 3 of my vehicles get the best mileage in the heat of Summer. The engine gets up to its optimum operating temperature much faster in the Summer. Cold engines drink fuel.
You only have 32.7 miles on this fill/trip A. Is trip A used for random distance or your distance from filling as some people do? If you're driving the same routes in the same density of traffic, and not idling more than usual, give it a hundred or two hundred before judging. If it continues, could have an issue with your car, too.I've never witnessed this before in the summer, but ever since the latest heatwave I've lost a ton of MPGs with this Integra. I used to average 30-31, now I'm at 23-25 which is ridiculous for this tiny car. I realize the air is less dense, but I've never noticed this in other vehicles in the summer.
Aren't most AC compressors in modern vehicles on all winter too to dehumidify?
Can’t speak for all cars, but our van and truck will run the ac if you select defrost.
If that’s a per tank average give it a bit more miles to average out, my truck is always wildly off the first ~30 miles on the trip display which resets when I reset the trip miles vs the “rolling” average which never resets unless I force it. Also hand calculate it and see if the computer is just way out of whack.
That's the only thing I can think of, unless the extreme heat is causing fuel to somehow evaporate and leave the tank into the atmosphere? Which shouldn't happen, and you'd probably smell it. It has been hot in NY, and I find myself turning the AC on a few seconds after starting the engine, typically I'll drive a little first.
Absolutely agree this is the issue.
I also notice your trip meter is at 32 miles which means your avg fuel economy over the last 32 miles at 23 mpg. Not exactly meaningful.
Report back after 350 miles (tank) and guessing will raise up.
Report back after 350 miles (tank) and guessing will raise up.
Last edited:
As others have mentioned, sample space for current tank isn't sufficient nor are the measurements accurate enough.
I typically average just under 30MPG in my Mazda3, but can have the occasional tank that is 25-26MPG. I've probably spent time idling waiting for a customer, or a part, or sitting in my car taking a conference call or similar as I'm out between tasks, etc.
Gather data from several full tanks and if really concerned, try to keep some notes on where you went and the sort of traffic conditions. I.E. interstate, urban freeway, stop and go traffic, etc. Distance traveled and time from start to destination would also give some clues.
Just some thoughts.
Or just drive and enjoy the car.
I typically average just under 30MPG in my Mazda3, but can have the occasional tank that is 25-26MPG. I've probably spent time idling waiting for a customer, or a part, or sitting in my car taking a conference call or similar as I'm out between tasks, etc.
Gather data from several full tanks and if really concerned, try to keep some notes on where you went and the sort of traffic conditions. I.E. interstate, urban freeway, stop and go traffic, etc. Distance traveled and time from start to destination would also give some clues.
Just some thoughts.
Or just drive and enjoy the car.
Hermann
Site Donor 2023
MAF sensor needs cleaning?I've never witnessed this before in the summer, but ever since the latest heatwave I've lost a ton of MPGs with this Integra. I used to average 30-31, now I'm at 23-25 which is ridiculous for this tiny car. I realize the air is less dense, but I've never noticed this in other vehicles in the summer.
Hot weather shouldn't affect fuel economy substantially. I would do more checks on your fuel mileage.
Maybe your fuel has a new formulation and you should try a different brand? You're in Phoenix. If your station is somehow getting the special gasoline formulated for California, that + the heat could make a difference.
I believe it is your fuel.
I suggest trying Shell 93 octane as an experiment.
I'm having big-time trouble with fuel related MPG on my older Jag (as low as 8mpg vs. 27) (mostly related to octane scams when I am in NY). The Shell stations seem to be the only solution, likely due to an unadulterated product. I've started using the Shell 93 in my newer Jag, and it loves it too.
In years past, the Chevron stations gave the best results. That is no longer so.
I suggest trying Shell 93 octane as an experiment.
I'm having big-time trouble with fuel related MPG on my older Jag (as low as 8mpg vs. 27) (mostly related to octane scams when I am in NY). The Shell stations seem to be the only solution, likely due to an unadulterated product. I've started using the Shell 93 in my newer Jag, and it loves it too.
In years past, the Chevron stations gave the best results. That is no longer so.
NO. It should be generally more efficient.I've never witnessed this before in the summer, but ever since the latest heatwave I've lost a ton of MPGs with this Integra. I used to average 30-31, now I'm at 23-25 which is ridiculous for this tiny car. I realize the air is less dense, but I've never noticed this in other vehicles in the summer.
That car is 1-3/4 tonnes with driver and not "tiny" with size and weighs very close to the mid-sized 7th gen Accord
Just noticed it's a new car;
1.5 Turbo DI? How carbon fluffy black is the tail pipe? How is the oil level?
I say Give it another 200 mile cycle with fresh fuel.
Was this assertion Based this on the 34 mile trip as displayed on you DIC ? - That's not conclusive data.
What octane does it require? I find middle-grade (AKI r+m/2) "Premium" fuels often un-pumped and stale. So, I would use 87. Or blend you own by pumping twice 3/4 of 87 then 1/4 of 93AKI) My search shows Costco is Top Tier additised fuel. That is pretty much required these days. You didn't add any extra cleansers did you? That would be too much detergent = BAD.
Did you just replace that moly laden FF break-in oil? '
You are in the "dregs of engine wear in" where the engine is not particularly happy.
Somtimes I start my car, don't let it warm up for a 1/2 min to go closed loop and dirve off and the thing, it won't run right. Experienced this too many tomes. If I can stop, shut her down for 3-5min and reboot - many time that will get it back to good running.
But a proper running Honda? Typically No way that low on mpg. But the super high compression D.I turbos may need special care and feeding. It may be pulling timing and covering pre-ignition knock with over-fueling.
And just to be thorough, insure there are no squirrels or 'munks taking up residence in the airbox.
- Ken
Last edited:
Similar threads
