JDMPIRE_69

I WORK AROUND 20 MILES FROM HOME ALL FREEWAY MILES,I FILL MY CAR UP AND ON DAY 4 MY CAR IS EMPTY.PEOPLE WITH TRUCKS HAVE BETTER GAS MILAGE THAN ME AND IM IN A HONDA.WHAT CAN BE THE PROBLEM WITH MY CAR?IVE CHANGED AIR FILTER,SPARK PLUGS AND DID A OIL CHANGE ON IT.PLZ HELP!!!!

MAD_MIKE

Have you ever changed the O2 sensor? Only use Denso/NTK.
CEL on or any codes present?
At what speed do you travel?
Tires inflated correctly?
Alignment?
Your in Ca, does your area require a smog check? Post up the lastest test results.
How many miles on the car?

More information on the car and your driving habits would help diagnose any possible issues.

ss_zoidberg

Timing been checked?

JDMPIRE_69

HAVNT CHECKED THE O2 SENSOR BUT I DO HAVE A BAD EXHAUST LEAK MY CAR IS KINDA LOUD BUT I DIDNT THINK THAT WOULD BE THE ISSUE,MAYBE I SHOULD GET NEW PIPING TOMORROW.I DRIVE A 97 ACCORD SEDAN NEW RIMS AND TIRES I USE 89 GASOLINE,I TRAVEL SPEED OF 70-75 ALWAYS I FIGURE I NEED A ALIGNMENT BECAUSE THE RIMS I BAUGHT ARE REALLY WIDE LOW OFFSET RIMS BUT IT HAD BAD GAS MILAGE ON MY STOCK RIMS AS WELL.YES SOUTHERN CALI REQUIRES A SMOG CHECK I HAVE UNTIL THE END OF THE MONTH TO DO IT.150,XXX MILES TIMING BELT HSNT BEEN CHANGED I RECENTLY GOT THE CAR 4 MONTHS AGO. AND THANK YOU BOTH VERY MUCH FOR THE INFO

holmesnmanny

What size are your wheels ? Wheels that are bigger than stock will throw off both your tripometer and odomoter as well as your speedometer...making you think you're not getting as many miles as you think you are. Your speedometer is based on the circumference of your stock wheels.

Hooligan90

When is the last time you did a major tuneup? I.E.:Distributor cap and rotor, NGK plugs and wires, air filter, fuel filter, oil and filter (I recommend Royal Purple oil and filter), PCV valve and grommet? I had horrible gas milage when I got my CB7 with a stock 2.2 F22A4. Went through a tank in about 4 days. After I did the tuneup, replaced the air boost val and FITV,and cleaned the throttle body, my motor woke back up and I got way better gas mileage. 220 miles and I was just below half a tank.

TheMuffinMan

iTrader: (1)

The timing belt hasn't been changed at 150k miles? You're flirting with danger.

- use regular gas, 89 and 93 are wasted on the car
- tire pressure should be 32 PSI cold
- if you have heavy *** wheels and tires that will affect your mileage
- timing belt/water pump/coolant/gaskets/etc should all be changed immediately (you should be on your third timing belt/water pump by this point)
- read the other gas mileage threads & stop using CAPS

JDMPIRE_69

WELL MY GAS MILAGE WAS STILL HORRIBLE WHEN I WAS ON MY STOCK ACCORD RIMS,NOW IM ON 16" RIMS 205/50/17 TIRES.AND H22 REF"D IN UR CB??NICE!!! why do u think 89 gasoline is a waist?and im not positive that the car hasnt has timing changed im assuming i just got the car 3 months ago.so far ive only done new spark plugs,new radiator fluids and new hoses.previous owner had tranny flushed and serpentine belts new put on.havnt done distributor cap and rotor yet but how am i to know if it needs changed i dont want to waist unnessicary money.wow!!!so u had the same problem as me with ur cb huh.well theres my answer ima do exactli waht u did.
thank u all for the advice i really appreciate it!!!

JDMPIRE_69

"205/50/16"

TheMuffinMan

iTrader: (1)

I don't think you understand octane ratings - anything above what the manufacturer recommends a waste because

1) The car isn't tuned for it
2) You have a low compression motor that can't benefit from it

http://www.consumer.ftc.gov/articles...ctane-gasoline

Very few cars take advantage of premium over the recommended regular.

doc500

What TheMuffinMan is trying to say, is do ALL of the maintenance work. It is never a waste of money to take care of the vehicle correctly. Also, you might want to run a compression check, and leakdown test on the car.

jdowen2

What is your MPG? A side note: I worked with a guy who siphoned gas out of his neighbors car just to mess with his head.

bairdandrew77

Might be your fuel cap. My Accord sucked more gas than my F350 and it turned out to be the fuel cap.
P.S. If you do replace it, get a Honda cap, NOT Autozone.

Sl0wH0nda

Did you say there was any CEL's on or not? The first thing that popped into my head would be O2 sensor but definantly a good tune up can make a wonder of difference but then again it could be something simple like bairdandrew said being a gas cap, I always start with the cheapest parts first and if its not those, well you have a nice tuneup ect along with figuring out what was causing it but I'm putting money on the 02 sensor(s).

JDMPIRE_69

ok thx alot guys ill give all ur advice a shot!

holmesnmanny

OP, I'm curious as to how you're calculating your mpg's.

Do this. Fill your car up. Set the tripometer to 0. Drive about 300 miles....doesn't have to be exact Fill your car up again. Look at how many miles are on your tripometer..exactly... and divide that same number by how many gallons it takes to fill up....exactly. Report the numbers here.

Hooligan90

Any update?

Larryef9

I have the same issue I have a 89 civic ef sedan & it gives me bad gas mileage the has about 190xxx just recently did a auto to 5 speed swap love it lol I have straight pipe I've changed the spark plugs & oil I'm on a budget since I just turned 18 & my gf is 6 months pregnant I don't have a lot of money to spend I've been told to change my fuel filter to get better mileage any suggestions on that ?

tim73

Your car monitors the air fuel mixture, one of two ways. When you first start the vehicle, it looks at the ECT until the engine is up to normal operating temperature. If it never sees the corect temperature, it will assume the engine is still not warm enough and will keep dumping fuel into the engine. That will give you bad gas mileage. Also, once the engine sees the correct temperature, it will swap over tot he O2 sensor(s) if they are bad...or non existent. The computer will not see the correct "o2" level in the exhaust and will keep dumping fuel in it, looking fo rthe correct value. Also, if you have an exhaust leak in bewteen the engien and the O2 sensor it will affect the O2 sensors performance...and therefor gas mileage.

Check your ECT, and then check you O2 sensors...make sure you have no exhaust leaks.

Larryef9

What's a ECT & how do can you tell if the O2 sensor is bad. ?

rockycat

Does the new poster's realize that when this OLD thread was started gas was 3.50-4.00 dollars a gallon? O2 sensors that are out of range will set a cel.

tim73

ECT=Engine Coolant Temperature

MAD_MIKE

Probably would get better insight from the EF Civic forum for any particular chassis related issues, than from the Accord forum.

Check the basics, color of spark, compression psi, fuel psi, check for any stored codes, verify spark plugs/wires are within spec, etc.

Are you positive you changed everything over correctly for the 5spd swap? Verify the gears/final drive of the transmission? Not lingering in low gears excessively?