Crapy Mileage

[L Squared]

Hey all,
It's been a while since i've posted. I do have a question/problem.
My mileage had dropped from between 27-29mpg to 20-25mpg with 23mpg being the most common mileage i've noticed. And there was a day that the car didn't want to stay at an idle. it only happened once tho and has seemed to stop. So what could cause this? My friend had a hunch it's an O2 sensor. If so where do i find it and replace it. If it's not the O2 sensor what else could it be? I'm kinda at a loss.

Just to add another possibility is it possible that my odometer isn't working correctly? It seems like i'm traveling the same ammount on a tank of gas with out a refuel, about once a week.

Lemme know what you think.

Thanks again!

-L²

[ACCORD EX]

i don't think it's the odo meter !

MIKE

['89AccordLX(Rus)]

Change the airfilter first and see if that makes any difference. You can also change the fuel filter(however it would probably not affect your mileage).

Because you say the engine had a problem with idling I would assume it is an engine problem. You can test your sensor as well. The procedure is outlined in the shop manual which can be downloaded at Paul's site:

Shop Manual (http://www.pauldesign.ru/honda/shopmanual.html)

Before you start dumping money into replacement parts, test your current ones for malfunctioning. :D

[anchovies]

When was the last time you did a tune up?

[L Squared]

Hey guys,
To awnser your questions...the engine was actually rebuilt in april. So i don't think a tune up is needed just yet. The idle problem only happened once. Dunno what it was maybe something sticking until the engine got hot i assume.

I was looking at the tires and they seemed rather low for i filled all of them to 35 psi and actually i think that solved my problem I have a hard time beleiving that my milage can drop that much just because each tire was 5 to 10 lbs low in each tire. I'm gonna run around town for another week and see what it does.

Any thoughts on this?

Thanks again!

-L²

['89AccordLX(Rus)]

I run 28 psi all around on my Accord. Decided to go by the label on the driverside door post and since it said 26 psi, I went with 28.:tongue: Tire pressure will greately affect your car's performance and fuel economy. The reasons for that are:

1.) An under-inflated tire's contact surface (the contact b/w the road and tire) is greater than the contact surface of a properly inflated tire. This causes increased friction between the road and the tire which leads to more resistance during motion. Since now the engine needs to work much harder to push the car along, your fuel economy is compromised.

2.)Since an underinflated tire has more friction with the road, it tends to build up heat. Heat is the primary cause of the tires disintegrating at high speed. Driving with your tires underinflated is very dangerous. In most cases prolonged high-speed driving will cause a blow-out.

P.S.: If you over-inflate your tires, you may experience a very rough ride since now your tires don't absorb any shock or as much feedback from the road. Since your tires are inflated to 35, you should still be safe to drive but do check the maximum inflation rating on the sidewall of the tire. Over-inflation can cause a blow-out as well.

[dosh8er]

from experience, at the ex-job, and my own vehicles, 34 psi is a good pressure to set the tires to. The max on our tires (stock) is 35 psi by tire manufacture, and although honda recommends 28, or 26, those are for comfort, not just milage. If you were to increase your psi to about 34 from 28ish, you'd notice a jump in milage, and not a significant drop in comfort in ride.

Always measure tires cold.

Getting back to yer other problem, I think it might have something to do with gasoline (petrol as some say on the board). I noticed the same decrease in milage. I started using high milage oil, and noticed the increase, but It eventually dropped, back down after several oil changes, so I'm wondering that it might be the type of fuel. I read somewhere that the gasoline in the winter is much different than the gasoline of the summer. It has to do with additives and such. That could be it.

But I had to increase my idle in the winter here, because it would idle too rough at what I had it set at... I think that's because the idle was set for the warm summer months, and now the winter has colder air, the engine runs slightly different. That could be something to do with it: the weather.

I'm also in the process of watching to see if my new water pump would make any difference. As strange as that sounds, I'm sure there's some truth in that. (bearings moving more freely than old one, better milage?)

There are many factors that could be making this milage drop... others could be right, it could be a sensor. That's what you get with an old car though...

[MoBFiGGa]

Mine to from like 420 miles to a tank to 300 im thinkin the o rings on fuel injectors check out yours see if there leaking all dirty and shit

[njpeter]

in some areas ( like the great state of NJ) we get different fuel in the winter..and less mileage..I'd say on average 5..cold weather also hurts mileage, as do all the things the other members mentioned. you may want to check for a dragging brake caliper ( feel the wheels after a long run ( carful..hot maybe) ...one really smokin hot rim is the tip off. Calipers do need some attention now and then

[AZmike]

Originally posted by MoBFiGGa
Mine to from like 420 miles to a tank to 300 im thinkin the o rings on fuel injectors check out yours see if there leaking all dirty and shit

I had bad leaks on 3 of my injectors. The seals were all in great condition. The seam in the injector between the plastic and metal parts was what was leaking on all three of them.

[AccordEpicenter]

dude its winter too, letting the car warm up costs gas, driving in cold weather does too because the intake temp gauge makes the engine richen up a bit. Ive been getting mileage like yours too.

[bobafett]

i too have been noticing a lot worse milage, i used to be getting 350 or so and still have a qtr tank left, now i am almost to the E line at 300....

[Mike's89AccordLX]

I was always told to check the tire pressure when the tires are warmed up. When they're cold they lose like 8psi and if you inflate them to 35psi when cold it would be like 43psi when warm causing them to be over inflated. I think it's better to check pressure and add air when the tires are warm.

[njpeter]

if you do it when they are hot, the pressure will be too low in the morning. All tire pressure specs always state (cold).