I have a 92 accord with 230,000 on it.

I used to get about 420 miles to a tank... then about a year or so ago it went down to 360. Now I am lucky to get 320.

It has no mods. I do all of the regular maint on it like air filter, plugs, wires cap, rotor, fuel filter, etc. I have never touched the injectors and the timing belt is overdue at 180K miles.

I don't drive any differently than I did before - actually took it easy for 3 tanks and still no change.

It does not seem to have lost any power.

Is there anything that I might be missing or is this just a symptom of the car getting old?

If anybody has some ideas and wants me to do some tests, I can do it.

 

o2 sensor maybe? leaky injectors? Change that t-belt asap otherwise your're gonna spend 2 grand to get the problem fixed if it breaks.

 

well you car is what 14yrs old. But look at the fuel injector, you might have a leaky fuel injector. Also when was that last time you took your car in, or did your own tune up on the engine? That's all I can think of.

 

just because the car is 14 years old does not mean that it will have problems. I'd be more concered about the t-belt

your gas milage is off because your timing is off. I'd replace the belt before I did anything else to the car. cost is about 290-400 depending upon where you go.

 

how much is a new timing belt? and why so much? is it that difficult to do?

 

Lazy O2 sensor(s).
It will require a OBD1 scan tool, a digital multimeter and a print out of the procedure. What you will be looking for is a value called Cross-counts. This is a measurement of how many times the O2 sensor reads variations in full Range Lean to Full Range Rich. The important point is not that it's doing this, but more-so how many times it does this within a specific period of time, and how quickly it reacts.
In effect, as the O2 sensor ages; it becomes increasingly desensitized, and can't keep up with these Mixture Range changes (It gets "Lazy"). With this increased inefficiency, gas mileage decreases.
If the "Usual Suspects" check out (the normal "Mileage Hot spots"), have the O2 sensor(s) checked out.

P




Modified by P_Adams at 10:44 PM 12/20/2005

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mac_24_seven &raquo;</TD></TR><TR><TD CLASS="quote">how much is a new timing belt? and why so much? is it that difficult to do?</TD></TR></TABLE>

Since I am lazy in the winter time and it is really cold I let the Honda dealer do it. it cost me $360 in 2001

 

Adding air into my tires added 20+ miles per fill up.

 

i don't how much it cost.. but i know that changing it isn't easy... ....it's a tricky thing....

 

I also have a 92 EX with a few more miles that experienced the exact same drop in gas mileage. Gas prices being what they are, I decided that it was finaly worth the time and effort to find the problem(s). My problems were a clogged EGR system and a starting(booster) valve that would not hold vacuum. I had to remove the Intake manifold to thoroughly clean out the EGR ports. Where they terminate in the manifold cannot be seen and they must be felt with a 1/8 piece of wire or something similar and the carbon poked out of them. With everything disassembled on the T.B. and I.M. , I found that all of the orings and seals were flat and brittle. They were cheap so I replaced ALL seals including the fuel injector seals. By the way, I'm not saying it doesn't happen because it does, but, in over 25 years of working on cars I've only seen one bad injector. If you had one stuck open you would see evidence of that on one of your plugs. You will also get people on this sight that will argue over the EGR's and vacuum's effect on mileage. These are the things I fixed and my mileage went back up to about 27 MPG. Not quite the 28-29 that I used to get when it was younger but better than 22.

 

I'm not arguing w/you, simply gonan state my experience w/clogged EGR.
I was throwin a CEL a month or so ago and the clogged EGR ports were what was doin it.
now, the CEL light came on while i was on a trip to tenn. i actually got the best gas mileage i had ever got b4..37.7 on one tank and 35.X on the next..WITH the clogged EGR. I did the required procedure to clean em, off goes the CEL and i've been getting normal mileage (31-34) ever since.. but i have not tried to get the uber mileage i was tryin to get up there either...

so I didnt notice ANY drop in mileage at all..and the ports were 100% clogged. i can see the other problems ADDED to the clogged EGR messin up your mileage, but in my case, I noticed no negative effect at all. its a 96 ex w/140,4XX on it.

 

Thats not really apples to apples. You have a different engine with OBDII. I also replaced my O2 sensor about a month before I fixed the EGR to get rid of a code 43 and did not see a mileage increase which is why I dug deeper. I don't dispute your experience on your particular car with a different emmissions and engine management system. I wish a F22A6 could get even your worse gas mileage.

 

Everybody - thanks for the replies.

I have been nursing a bad tranny for about 20K miles - I have to change the fluid every 5000 miles or else it slips so much it won't run - so I don't know how much I really care about doing a timing belt or the longevity of the car. I need to decide what to do about the tranny.

I want to get 239,000 miles out of a car to feel like it was a good car - distance from the earth to the moon.

I can do the timing belt myself, I have just not been so inclined... yet. It is cold, and I don't have a lot going on since xmas is over, so maybe I will do it. I just did not want to do it, have the tranny go south and regret it.

I will check out some of the other advice offered here. The plugs have been fine, so I doubt that an injector is leaking or the timing is WAY off... but it does not have to be way off to matter that much. It kills me because the power is still as good as I can remember it being.

I checked air and tire size (thinking that maybe I had gotten bigger tires without remembering), but they are fine.

I tried acetone in the gas, and that really helped the power and idle, but did not help the mileage at all.

Oh, I checked the compression and all 4 cylinders were within 1 lb of each other and right near the factory spec. This is one good engine... so mabye I will invest in the belt and tranny.

Any other ideas?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jdadams12 &raquo;</TD></TR><TR><TD CLASS="quote">Everybody - thanks for the replies.

I have been nursing a bad tranny for about 20K miles - I have to change the fluid every 5000 miles or else it slips so much it won't run - so I don't know how much I really care about doing a timing belt or the longevity of the car. I need to decide what to do about the tranny.

I want to get 239,000 miles out of a car to feel like it was a good car - distance from the earth to the moon.

I can do the timing belt myself, I have just not been so inclined... yet. It is cold, and I don't have a lot going on since xmas is over, so maybe I will do it. I just did not want to do it, have the tranny go south and regret it.

I will check out some of the other advice offered here. The plugs have been fine, so I doubt that an injector is leaking or the timing is WAY off... but it does not have to be way off to matter that much. It kills me because the power is still as good as I can remember it being.

I checked air and tire size (thinking that maybe I had gotten bigger tires without remembering), but they are fine.

I tried acetone in the gas, and that really helped the power and idle, but did not help the mileage at all.

Oh, I checked the compression and all 4 cylinders were within 1 lb of each other and right near the factory spec. This is one good engine... so mabye I will invest in the belt and tranny.

Any other ideas?</TD></TR></TABLE>

Any thoughts that maybe the tranny slipping has an effect on the mileage????

 

It does not slip. That is why I change the fluid. Besides, mileage went south before the tranny did.

 

Winter addittives in different parts of the country are something else that might be considered

 

Now I'll admit I don't know the first thing about auto trannys (and frankly have no desire to learn) but do they transfer power by direct gearing like a manual or is it fluid motion. It sounds weird but the reason I ask is because if its the movement of fluid then broken down seals and whatnot may cause it to slip (as mentioned) and for fluid to pass by seals. This could cause a loss of torque or even added resistance. Does the car coast noticably better in neutral?

Also where are we at with the O2 diagnostic? To do it right you really need to hook up a good voltmeter and check resistance (it is resistance right?, its been a while)