What happened to my fuel mileage?

[sb001]

Couple months ago I introduced myself on this board as the new owner of a 1998 Accord 4cyl sedan. I had been getting around 28-29mpg in mixed city/ highway driving up until this point (not optimal but acceptable.) I check the mpg the usual way- by resetting the trip odometer after every fillup, then next fillup I take the mileage travelled and divide by gallons consumed.
I got a new job recently in another town about 40 minutes away from my house, and discovered my fuel mileage dropping just a bit (but I accepted this as more city driving- where I live I have to take a few back roads to get to a highway, and cut through a few small towns.) On my last fill up I reset the trip odometer, and looking at it today my tank is about half full, yet I have only gone 160 miles!!! My tank is 17.1 gallons (if I remember correctly) so if I take half that (8.55) and divide into 160, it comes out to 18.7mpg!!!! That IS unacceptable!! WTF???

 

[ryannel2003]

Are you dividing that amount by the fuel you put in or the gauge itself? I find that even when my Accord gauge reached the halfway point I hadn't actually used half a tank. That said, any changed in how the car runs? When was the last time the plugs were changed? Air filter? Is the tire pressure ok?

 

[agginline86]

If you're refueling when the light comes on, you aren't putting more than 15 gallons, but your fuel gauges are not to "scale"

so half full isn't exactly half. I would reset you odo fill up all the way, drive, then when you refuel next divide by how much you put in

but have you done any maintenance or anything recently?

 

[sb001]

Part of the problem I am sure is that the temp has gone up where I live and the AC is using more engine power. But still, 18mpg?? That's worse than what I got in my 2007 Accord V6 way back when I had money
I have noticed recently, over the last few days, that the engine struggles just a bit to provide torque at low speeds- for example when I turn at an intersection corner say about 10mph, I drop into 2nd (it's a 5 speed manual), it takes a few seconds to provide pickup power before the car starts to accelerate again once I hit the gas coming out of the turn. It does not provide an immediate response. I'll check some things when I get home but I have checked the plugs fairly recently (few weeks ago) and they seemed fine. Air filter may need replacing, and it could use an oil change, but overall it drives great, very smooth with no weird issues. Just... 18mpg???

 

[sb001]

If you're refueling when the light comes on, you aren't putting more than 15 gallons, but your fuel gauges are not to "scale"

so half full isn't exactly half. I would reset you odo fill up all the way, drive, then when you refuel next divide by how much you put in

but have you done any maintenance or anything recently?

I don't usually refuel RIGHT when the light comes on, wait until it's below 1/8 of a tank left- and I do NOT top off at the pump, when it clicks off that's it. I suppose it's possible that the gauge is a bit off and the tank is still above half full. Still... even if I assume it's still got 10 gallons left (which would mean the gauge is pretty far off), that would be 7.1 gallons consumed. 160/7.1= 22.5 mpg. That's still pretty unacceptable to me.

 

[agginline86]

I don't usually refuel RIGHT when the light comes on, wait until it's below 1/8 of a tank left- and I do NOT top off at the pump, when it clicks off that's it. I suppose it's possible that the gauge is a bit off and the tank is still above half full. Still... even if I assume it's still got 10 gallons left (which would mean the gauge is pretty far off), that would be 7.1 gallons consumed. 160/7.1= 22.5 mpg. That's still pretty unacceptable to me.

pretty sure City MPG for our cars is 21 MPG. 29 MPG Highway for Manual Trans

19 City / 27 Highway for autos

 

[sb001]

pretty sure City MPG for our cars is 21 MPG. 29 MPG Highway for Manual Trans

19 City / 27 Highway for autos

4 banger 5 speed manual is supposed to be 22/28/24 combined. However everything I have ever read, heard, or experienced with the 6th gen Accord 4 cyl VTEC said it got better than advertised gas mileage. And as I stated earlier mine was getting 28-29 combined before. So I still need to know what has happened. I will admit AC may explain a large chunk of it

 

[agginline86]

4 banger 5 speed manual is supposed to be 22/28/24 combined. However everything I have ever read, heard, or experienced with the 6th gen Accord 4 cyl VTEC said it got better than advertised gas mileage. And as I stated earlier mine was getting 28-29 combined before. So I still need to know what has happened. I will admit AC may explain a large chunk of it

City driving kills your MPG quick. your experience sounds completely normal

 

[xci.ed6]

Fill it up!

How many gallons/miles?

The gauge usuall says 1/2 around 10 gallons LEFT!

 

[shngbns]

I would like to know how to fix this too. I get around 300 miles on a tank. Sometimes less.