Well I have a 98 Honda Civic Hx w/ 65k miles. While cruising the net trying to find how much my Civic is worth (she is being sold) I started seeing post about getting 40+mpg hwy on HX's. How can this be? All these years I have owned the car I can't get more than 30mpg hwy. I don't accelerate hard but do cruise at 75 due to long straight highways here. So why am I getting such bad fuel mileage? I wish I would have known I could get 40+ mpg I would not have racked up so many miles on my motorcycles.

So if anyone has a clue I would love to hear your answer!!

 

a good tune up ... i have a vx which is close to the hx and i get about 43 or so mpg

 

well alot of it is your driving habits.. popping it in nuetral and rolling to a stop at stop signs and red lights, or if you keep the car in gear and jump from the gas pedal to the brake to stop. and for best milage stick to 65mph and kick it on cruise control.
all depends on how you drive and if your cars had a recent tune up. dirty plugs, cap dirt fuel injectors can all effect milage.

and i dont know if it helps or not but after i give my vehicles a tune up i unplug the battery while doing so so the computer will relearn how the motor is running and driving. it might help and it might not.

and ^ EGs usually do get better milage they dont weigh as much due to more safety features in newer ej ek+

 

I bought the car w/ 11k miles on it from a old lady. It had just been certified at a dealership. Since the day I bought the car it has always got the same gas mileage. Only thing I could do that I havn't done recently is change the plugs and air filter. But would that really keep me from getting good gas mileage?

 

I never drive the thing and when I do it's commuting to work on the super slab doing 76mph. If i did go 65 I would get run over
Addictiontobass I havn't changed the plugs or cap. Wow I can't believe those things can really throw my mileage off.

 

i get 30mpg in my crx si driving aggresively
i got 52mpg in my 93 cx hatch when i was hypermiling
both 5 speed
i could have exceded 60mpg in your hx hypermiling

 

they can.....
the distributor cap and the distributors rotor button if they are dirty or corded or just worn it could be giving a weak spark, just like the spark plug wires if they are cracked they can corrode inside and hurt the spark also.
and the spark plugs wear all the time and the spark gap gets larger giving it a weaker spark also.
i would at least pull the spark plugs and check the gaps and clean them or just replace them with some good plugs. ive heard that some E3 plugs are suposed to give you better milage but no idea but id like to try them in my truck eventually.
and even with new plugs if you can check the gaps... some spark plugs you cannt check the gap easily.

but mostly MPG depends on your driving habits.

 

this is what honda stats your civc's mpg should have

.................................................. .................................city hwy
1998 Honda Civic HX 4 cylinder 1.6 liter R (M5) Manual 36 44

 

Ohh my. Well I'm selling the car anyways. But after reading these posts and seeing what I should be getting for mpg, I think I will change the plugs and pop a new air filter in, since those are jobs I can do easily. I know my plug wires are ok because I keep my engine very clean. Looks like new still under the hood. Hopefully I will see a little difference in mpg. Wold love to have my car get the the same mpg as my bike 45!!

 

try changing the distributor cap and rotor also..maybe a new fuel filter.