Ok, I have a 97 ex coupe AUTOMATIC (4spd) with a D16Y8 in it. a little over 115k miles.

I am getting (since I got it a year ago) average 200 miles between fillups (I drive that thing down to about 1 gallon left according to the factory tank size)

I thought this was normal for a 10 yr old car. THERE ARE NO MODS except today I put a cherry bomb to replace my rusted muff...its cheaper, shut up. I'll do it right when the weather is warmer.

I don't drive that heavy,, but I live in a hilly area (north of philly, PA) so it shifts around 3, or 3.5k. I read that with 5spd, ppl shift at 2.5, whatever.

Any help would be appreciated

BTW I did all the 105k scheduled maintenance (timing belt, water pump, all belts, etc)


I know this thread is all over, but I read them all, and can't find the answer...
I have new oil, and air filter, and run on cheapo 89 gas with ethanol.

THANKS FOR THE INPUT




EDIT: CHEAPO 87 GAS


Modified by LemonLime at 6:53 PM 12/13/2007

 

Definately not normal like I said before.

I still get 30mpg normally around town in my 99 GSR with 157K. I get around 32-35 highway in the summer. The MPG drops a little in the winter since the car is in open loop longer.

My S2000 gets around 25 around town and like 32-36 highway. 26k miles. THat's all warm weather miles. I dont drive it in the winter. But even when I went road racing last summer...i checked my MPG just for the hell of it. I averaged like 18-20mpg combined highway/track.

There's something terribly wrong with your civic or driving habits if you're averaging 20mpg.

Are you measuring correctly?

 

I think i measure right...I have a log book, and every time I fill it up, i know how many gallons I just used. I combine that with the number on the trip odometer, to get Miles per Gallon, and then reset the trip (im not being a smart ***, just explaining for future questioners on this thread,...incase the thread survives, that is.... )

my habbits are to hurry when im in a hurry, but I don't floor it off every redlight....... i generally shift around 3 or 3.5 (like I said its an AUTO so I can't HELP IT! lol)

I don't even know where to start looking!!!

help?!?!

 

try running a higher grade fuel the next time u fill it up. i swear when i had my y8 it hated regular lol i was getting an average of 11mpg with it(head gasket issues and losing oil like woa) but i put 91 octane in it just for shitzengiggles and i wound up getting back up to 18mpg lol still not great but a hell of alot better.

 

might be worth a try, and for only a few bucks....cheaper than a new air filter!!! (for one tanks worth anyway...)

Thanks, but any ideas on WHY this is happening?

 

not a clue. i swapped the motor and tranny out before i figured it out. im inerested too because my accord gets pretty bad gas mileage too but idunno its my luck.

 

Why are we the only ones online???

LMAO

 

Bump for the MORNING

 

Btw, you have an 11.9 gallon tank.

 

I have the same problem in my em1, but I do drive like a stupid 17 year old, so that is probably why I get bad gas mileage.

 

yeah, 11.9 gallons - I usually need about 10 to fill her up. 9.5-10.5 and I always fill it up at or about 200 miles. Last week I only got like 175, but that was because I left it idling one day for an hour so my kid wouldn't wake up...he needed his naptime!!!

but even so, 200 miles to a tank is not what I expected when I bought this piece of ****...

 

Have you changed your Fuel filter? plugs?
I changed mine when i had a y8 and my MPG went up significantly

 

Have you checked for a CEL?

 

i thought ex's used 87 octane gas??

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dangthemang &raquo;</TD></TR><TR><TD CLASS="quote">i thought ex's used 87 octane gas?? </TD></TR></TABLE>
I use regular in my EX (which is recommended by Honda) and I get great gas mileage.

I need to start keeping track of mileage each tank again though.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dangthemang &raquo;</TD></TR><TR><TD CLASS="quote">i thought ex's used 87 octane gas?? </TD></TR></TABLE>

The do. Higher octane in a Y8 is nothing but a waste.

@ OP: Try getting an accurate gas mileage reading.

Not estimating what you pull off the factory gas gauge.

How to get an accurate gas mileage reading:

1) Go to a gas station and fill up your tank, reset the trip meter or note the mileage.
2) Drive until you've down to 1/4 or so.
3) Fill it up again and note the mileage.
4) Divide the total number of miles driven by the gallons and you got your MPG average.

NOTE: Do not fill up in between.

That's how you measure gas mileage, do it that way instead of estimating a % based on the fuel gauge...

What I'd recommend:
Do a full overhaul.
1) Put a bottle of seafoam in the gas tank, I wouldn't recommend feeding it into the crank case.
2) Change the oil, use 10w30, and oil filter.
3) Change the transmission fluid, lack of changing transmission fluid is the leading cause of automatic transmissions running inefficiently, it's even higher than people beating on it.
4) Change the distributor rotor, cap, igniter, spark plugs, and spark plug wires (use NGK for the spark plugs and wires).
5) Change fuel filter.

If you have no gains afterwards to a normal gas mileage, change out your fuel injectors. If one of your injectors is getting jammed open, it will cause gas mileage like that. It is NOT normal in any way.

Also, like NOFX has said, refer to the link here, and see if you're throwing any CEL's. If you are, please tell us what they are.

After you change out the injectors (or you might wanna do it before) since it's only $40 tops, put a fuel pressure gauge on the, it should read 43-48psi static reading when you unplug the vacuum line going from the fuel pressure regulator to the intake manifold.

If after you replace the injectors there's no change in the fuel mileage and/or the pressure is low, might wanna take a look at the fuel pressure regulator.

Also, are you using the stock ECU for that car? Should be a P2T.

Start with the basic stuff (tuneup) and work your way up, most likely it's an issue with the fuel system. A fuel filter can usually rip a few mpg off, but nothing incredibly bad - a jammed injector could kill ya though, but so could a combination of things.

I'd do a tuneup though before I look at that.

EDIT:
Thanks, Amy, for the heads up.


Modified by Syndacate at 7:21 PM 12/13/2007

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ifIexplode &raquo;</TD></TR><TR><TD CLASS="quote">Have you changed your Fuel filter? plugs?
I changed mine when i had a y8 and my MPG went up significantly </TD></TR></TABLE>

I'm still running plugs and fuel filter from factory, never replaced them.
And with 125k miles I'm still getting considerably over 30mpg. Just oil
changes.

 

^You might wanna think about a tune-up...if you can get the spark plugs out of the motor

 

1^^Yes i can get the plugs out, if I can find my 3/8 ratchet.......

BTW I DO KNOW HOW TO LOG MY MPG. I DO IT ONCE A WEEK EVERY FILLUP!!!
exactly as you stated, btw. I even write it down and sometimes transfer it to Excel.

thanks anyway.

2As for the plugs, ?I jsut bought NKGs but I don't know which ones. Are there different NKG options? I got the $2 buggers. Also got a bottle of injector cleaner (the prestone, not seafoam)


3Tranny flush is expensive, no?

4is it difficult to change the injectors? where are they?

5how do I know if I am throwing a CEL? I don't have any dash lights on....

Thanks for the help guys, HT FTW!

 

Also, no chip, that I know of, everything is stock (except for a new muff)

No CEL, sorry. If an injector was stuck open, wouldn't I run rich and throw a CEL?

 

get a new 02 sensor!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LemonLime &raquo;</TD></TR><TR><TD CLASS="quote">No CEL, sorry. If an injector was stuck open, wouldn't I run rich and throw a CEL?</TD></TR></TABLE>

You may not throw a code but you should see a lot of black smoke out of your new muff

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LemonLime &raquo;</TD></TR><TR><TD CLASS="quote">1^^Yes i can get the plugs out, if I can find my 3/8 ratchet.......I was just messing with the guy who has NEVER changed his...I've seen cases where people don't change them, and then try to...they ended up breaking the spark plug off in the head
BTW I DO KNOW HOW TO LOG MY MPG. I DO IT ONCE A WEEK EVERY FILLUP!!!
exactly as you stated, btw. I even write it down and sometimes transfer it to Excel.

thanks anyway.

2As for the plugs, ?I jsut bought NKGs but I don't know which ones. Are there different NKG options? I got the $2 buggers. Also got a bottle of injector cleaner (the prestone, not seafoam)


3Tranny flush is expensive, no? I wanna say our shop charges ~$100 for a fluid flush with genuine Honda ATFZ1 (the good stuff)

4is it difficult to change the injectors? where are they? They're right above your intake manifold/intake head ports...that general area

5how do I know if I am throwing a CEL? I don't have any dash lights on....When you turn your car on the CEL should light up for a few seconds, then go off. If your ECU had thrown a CEL, it would be on while driving.

Thanks for the help guys, HT FTW!
</TD></TR></TABLE>

My answers are in bold

 

Thanks, that helps a bit.

I think I might go ahead and just change the injectors...why not, right?

They can't be terribly expensive... as long as I already have the tools...

 

If you have any kind of stethascope (sp?), what doctors use (they make automotive ones that are more or less a rod instead of the circular pad), you can put that to the injectors while the car is running.

If it's making a constant tick noise, then they're firing correctly...if not, that means you have an issue.