Your fuel economy is reasonable with your practice of driving a “few miles a couple of times a week to exercise the engine”, those short trips will only yield about 15 miles per gallon.
As a follow on to @texases questions, what is the RPM level when you are cruising at a steady rate?
Yes, but that would be unusual on a car with this few miles. I expect the mpg you are getting is what you’d get with another sample of that same car; i.e. it has to do with the type of driving you do, where you drive, the ambient temperature, and the accuracy of your mpg calculations. There’s a slight chance you have a brake that is sticking. Feel the wheels after a drive, see if any of them are hot, or one is hotter than all the others.
But if you think it is still the engine, things that commonly cause poor mpg are
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coolant thermostat sticking open, preventing the engine from reaching the correct engine operating temperature. Test drive another new car matching your configuration, and see if the dash engine coolant temp gauge matches car to car once the engines warm up. If you are a scientific type, you could also measure the coolant temp directly using a non-contact laser gadget on the top radiator tank surface.
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engine coolant temp sensor inaccurate, causing the engine computer to inject more gas than it should. the engine computer will double pulse the injectors for example if it thinks the coolant is cold. this sensor’s calibration can usually be easily checked by a shop.
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less likely, faulty O2 sensor, or much less likely, faulty engine computer.
How’s the weather been in upstate NY lately? Cooler weather will adversely affect mileage. Especially as cold as it’s been getting at night now in the Northeast. My own mileage is exhibiting its annual mileage drop lately.
Apparently the OP has been complaining about the fuel mileage since he purchased vehicle in 2011. Until he tells us how he checks the MPG I can only assume he does not have a problem .
I write down how many gallons I put in when I add a full tank and then write down how many miles I got out of it when I run it till the gas light comes on. I fill up at the same gas station every time, a mobil.
How long are your trips? If you are never driving for more then 20minutes at a time your gas mileage will suffer. I get significantly worse mileage on short trips then I do on long drives, even if the short trips are mainly straight without much stopping or accelerating.
From the other topics posted, this is a car that gets less than 3000 miles a year and is driven maybe a couple times a week. This kind of driving will give the absolute worse mileage except for sitting in traffic. Its spending most of its time very rich just warming up and probably spitting raw gas into the oil. Take it on a 500 mile trip and see what the mileage is. It’ll help blow all the carbon out of it and loosen it up a little.
There’s nothing that a shop can look into during an oil change that will affect fuel economy. Well, except maybe tire pressure. But that’s not going to yield you 5mpg.
Why are you unhappy with your fuel economy? You don’t put nearly enough miles on the car to make it a financial issue and if you’re happy with the way the car runs just motor on.
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I drive more now. I didn’t drive as much this summer due to ankle surgery.
Wife had 4 cyl Camry with trip computer. She avg 25 mpg per tank and drive 1 mile to work, 5 days week. I believed trip computer. We used to hit mid 30’s on hwy trips with ease. Our caddy used to avg 14 mpg when she had that. U might say there is not enough time to screw up a 1 mile drive. Vs a 15 mi trip with 8 stoplights? Would we avg <25mpg on a 15 mile trip?
A friend of mine had the same issue with her Subaru Forrester. She took it to the dealer several times and they tried to tell her it only achieved the EPA mileage rating if she used a specific brand of gasoline (in this case, Chevron). She persisted and they finally figured out that the onboard computer was mis-programmed. After the computer issue was rectified the problem was solved.
I’m not sure if OP has yet told us what motor this Accord has
But if it’s got the V6 AND is used primarily for short trips, then the fuel economy is going to be fairly low, IMO
The 23/34 mpg cited would make it the 4-cyl.
Yes, I believe that makes perfect sense
The thing is a start up and slow driving heading to the highway can be a killer on mileage and can take quite a while for the average to come up again. When I commuted I’d spend maybe 10 minutes in town and then hit the freeway. I’d look at the average mpg calculator and reset it sometimes at home. Even though the car would get a good 27 on the freeway, it could take 10-15 miles driving on the freeway to get the average up again after the poor in town mileage. Just saying, 20 overall average may not be too far out of line. Best way is to just get it out on the road, warmed up, and reset the mileage calculator and see what it says after a half hour or so of constant speed driving. I can burn up a quarter tank or more in no time just tooling around town to the store etc. Yet if I get it out on the highway tht same quarter tank will take me over 100 miles.
It can be the vehicles fault and not be detectable. Before I retired, the company I worked for had two identical 2006 Malibu’s in there fleet. I used them on road trips many times. I always filled up when I started and again when I finished and then calculated the mileage. One of them got 34 mpg every time, the other got 32 every time.
I have found that the gas mileage changes some any time I change out a rear O2 sensor, but usually not much, 1 or 2 mpg. One thing that could have that big of an effect on mileage could be a very small fuel leak. It might take a sniffer to find it.
How did they solve the onboard computer issue with your friends Subaru? Did they have to replace the computer?
Even if they did have to replace the onboard computer on the car owned by Dakotaboy’s friend, are you willing to shoulder that cost with your car that is no longer covered by warranty?
As Bing stated, with your driving habits, low gas mileage is a given, and because of the non-warranty status of the car, I’m not sure if your driving habits warrant the “investment” of major amounts of money in the interest of gaining a few more miles per gallon.
It depends on if I could get honda to cover it under their warranty. It is documented I complained to the dealer multiple times about the gas mileage soon after buying the car. What kind of test would I tell them to run to see if the onboard computer if causing the issue?