Hello, I've got a 1996 Accord LX (non vtech 2.2L) and I don't think it's getting all that great of gas mileage. It gets about 20 mpg in town (babying it) and only about 23 mpg on the highway. I've replaced the plugs, plug wires, rotor, cap, air filter, pcv valve, and front o2 sensor all within the last couple of months. It's got a slightly rough idle, and sometimes it will idle (at the stop light) at ~650 rpm, and sometimes around 800 rpm. When you turn on the A/C at idle it really idles erratically for about 5 seconds and then smooths out some (I can still feel the vibration in the steering wheel). I'm not getting any fault codes from the computer, but I think that it's weird that it hardly gets any better mileage on the highway than it does in town. Also, I was thinking that 20 mpg in town is a bit low for a 4 banger like this. Does anyone have any ideas/suggestions?

Thanks in advance!!!

 

check the timing,
fuel filter
iac
doing a compression test wouldnt hurt.
air filter
adjust idle (use a handheld tach for precise adjustment)

thats all i cna think of for now.

 

Auto or Manual?

 

It's an automatic. As far as the timing goes, it's dead on 0*. Also, I did mention that the air filter had been replaced, and I've adjusted the idle up some, but idling it up isn't really a good solution to fixing the problem.

 

Hey if you ever get the chance to change your fuel filter. Tell me how it went. I just looked at my 97 Accord's and it was located right under the brake master cylinder. It looked like a hassle just to replace. So I didn't bother trying to replace it yet. Its almost due for a change so yeah. Good luck

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Charri &raquo;</TD></TR><TR><TD CLASS="quote">Hey if you ever get the chance to change your fuel filter. Tell me how it went. I just looked at my 97 Accord's and it was located right under the brake master cylinder. It looked like a hassle just to replace. So I didn't bother trying to replace it yet. Its almost due for a change so yeah. Good luck </TD></TR></TABLE>

yes it is a pain to change... just get it done at a shop (youll save urself a headache)... they charged me 90$ to do with them supplying the filter, and 50 for me bringing my own...

 

Wow, 90 bonez!!! I bought a fuel filter this last weekend for $21 (tax included) at Auto Zone. I got the fuel pressure released, no problem, and then I took the banjo bolt off the top of the filter. Everything was going smoothly until I had to take the fuel line off of the bottom of the filter. I had about 15* turning radius and the line was pretty much locked on to the filter. I couldn't get the damn line off so I said screw it and took the filter back. However, after getting that far myself and seeing what's involved, I'd say that $90 is pretty much a rip off for something like that. I didn't mention that you should be using a flare nut wrench to take off the fuel line, which I didn't have. That was probably the reason why I couldn't get it off. But heck, I'll just go out and buy one of those wrenches for $10 and get it taken care of; no way in hell I'd pay a mechanic that much money for a task like that. If you've got the correct wrench I'd say its about a 20 minute job.

But, back to my problem. The filter could possibly be my problem, but if it were clogged or almost clogged, I would think I'd notice some "surging" on the highway due to it not getting enough gas. I just had it out on the highway this weekend and didn't notice any surging.

Another thought I had is the IAC valve. With 95k miles on the car I'm thinking that that valve might be pretty carboned up. Are they cleanable? And does that seem to be a good step in trying to fix my problem?

 

you got a autozone filter.. i stick to oem usually... and depending on what year your vehicle is... it is a pain in the *** to change for a home mechanic...

and the iac valve is cleanable... i used a qtip with carb cleaner soaked o nthe tip and just wiped around till it blinged again.

 

Back to square one here. First i must say that this sort of problem is quite difficult to diagnos without seeing the car, but here are some ideas. First, please answer these questions:

1. Do you smell gas when you shut it down?
2. Do you smell rotten eggs?
3. Does it have the same power as before?

To high a fuel pressure will cause this, as well as to low of a fuel pressure. Now, you can, if you have the tools, test the pressure at the fuel filter if you wish.

Also a defective coolant temperature sensor can cause this since your engine may run a bit hotter than usual and not set a code. BTW this sensor is crucial to the operation of your engine and may cause a slew of problems. To test, do this:

1. tap into the signal wire of the sensor
2. measure voltage when engine is cold. Should be around 4 to 4.5 volts
3. start you car and let it warm up. You will see the voltage drop as it warms up. At operating temperature, i think you will see 1 or .5 volts.

If you see more than 4.9 to 5.1 volts you have an open circuit
if you see 0 volts, you have a ground problem.
if you get something else, post your results here.

Now you have done all the standard checks and replacements (spark plugs, timing, air filter, pcv, etc....), so without the cts and fuel pressure ruled out, i can't continue with ideas.

As for the IAC, yes they are cleanable. But sometimes, you can't clean them good. Also, it is very delicate. I would not mess with it unless i have to.

fs

 

1. No smell of gas when I shut it off

2. No smell of rotten eggs. But while it's running, the exhaust doesn't smell as "clean" as it should on a vehicle like that. I have smelled the rotten egg smell before (due to cat converter problems) and I know this smell I'm smelling is not it.

3. The car drives fine, sometimes it feels like it shifts a little too early (I'm used to a 350 Turbo Hydromatic powered by a 350 ; - ) It's just the rough idle and not so good gas mileage.


On the note of the coolant sensor, it will trigger a fault code if it is not functional, right?

 

For the cts. If it is not functional yes, but if it is out of range a bit, no....

But, simply out of curiosity, why do you say you are not getting good gas mileage???

You see, i have noticed, on my personal cars and motorcycles, that cheap gas can really bring your MPG down. AN example was with one of my motorcycles not to long ago. 5 gallons usually gets me about 200 miles but i fueled up at a cheapy station and it only brought me 165 miles.

So when have you noticed this? and how long has this been going on, and what brand of gas do you use?

fs

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by filthy_shovel &raquo;</TD></TR><TR><TD CLASS="quote">
But, simply out of curiosity, why do you say you are not getting good gas mileage???
</TD></TR></TABLE>

well, from the specs i've read, a 1996 Honda Accord 2.2L (4 banger), should be getting about 25 mpg in town, and about 32 mpg on the highway. Mine gets about 20 in town, and about 23 on the highway.


<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by filthy_shovel &raquo;</TD></TR><TR><TD CLASS="quote">
So when have you noticed this? and how long has this been going on, and what brand of gas do you use?
</TD></TR></TABLE>

I've noticed this about 8 months ago, and I use 87 octane at Ammoco.

 

If you are not smelling gas, and such, then i think we can rule out unburnt fuel (ignition problem) and exhaust problems.

So, is it possible that it is starving for fuel???? Could be... Check fuel pressur eat the filter. Unplug the fuel line after the filter, and give it a crank. The fuel should come out at a decent flow. If it dribbles, then you found your problem, if not, then you need to move to other things...

fs

 

If I were you, I would get the injectors cleaned. Most places have the three step cleaning process that works with the injectors still on the car and the engine running. This will work, but I would suggest finding a place that has a bench cleaning system like the ASNU system. They will measure the flow of each injector, and then they will basically use a sonic cleaner to get rid of all the crap. Injectors with screens in them will get the screens replaced, and they will usually replace all of the orings then reinstall. If you can get the injectors off yourself, you will save some money.
This is the best injector cleaning system I have ever seen, but I have also had good experiences with the on-car cleaning systems.

I would go this route.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by filthy_shovel &raquo;</TD></TR><TR><TD CLASS="quote">Also a defective coolant temperature sensor can cause this since your engine may run a bit hotter than usual and not set a code. BTW this sensor is crucial to the operation of your engine and may cause a slew of problems. To test, do this:

</TD></TR></TABLE>

Fifty Shovel - I am not trying to be confrontational, but I don't agree with your statement above. On fuel injected cars, the hotter the car runs, the better (to a point) I can't remember if the 96 is OBDI or OBDII, but if it is OBDII it will be more noticeable than the OBDI.
On the other hand, if the vehicle does not go into closed loop, it will run richer, and burn more fuel.

 

...how could adding fuel improve gas milage?

 

Ok, I'm going to attempt replacing the fuel filter again myself. This time I'm going to get the proper tool ; - ) What size of flare nut wrench should I get to remove the fuel line? I've got to go out and buy this and I don't want to buy a whole set; kinda broke.

 

Try checking the size with a regular wrench to figure out exactly what you need, then go buy the proper size.

 

Ok, I went out and got the right size flare nut wrench. No f*#!ing luck at all. That original filter is LOCKED on there. Looks like I'll have to pay the mechanic the "rip off fee" of $90. Anywho, I hooked up a vacuum gauge just to see how it was reading and I'm getting way too much vacuum I think. 22" hg at idle (~750 rpm) is not right, is it? I'm used to working on cam'd out 350 SBCs with about 11" vacuum. I know things are different with a 2.2L 4 banger, but that just seems ridiculously high.

 

bump idee bump!