Hi, I got a Accord 2001 4 cyl. f23a automatic. The car have 160 000 miles. Since a month I got very poor gaz mileage and I don't know why, I use half a gallon more in city and highway driving. I've not changed my driving. There's no check engine...I've cleaned my pcv valve. Some people tell me, maybe the problem is a clogged fuel filter...Can somebody help me!!

I've changed:
-Plugs iridium NGK
-Air filter FRAM
-Wires
-Distributor cap
-Rotor
-Valves have been ajusted.

Never changed:
-Tranny have 60 000miles never changed oil

Thanks!

 

Nobody can help me?

 

is ur check engine light on?

 

If its not u might wanna look into replacing ur filter or maybe even ur pump. N just to let u know get ur dang trani serviced for the love of god! If its manual u might wanna think bout replacin ur clutch soon as well. General rule of thumb for trani's, autos get serviced @ 20k-30k miles n mans get serviced @ 50k-60k miles. I use 5 speeds n I change my fluid @ 20k just bcause I've had my bearings implode on me n tranis aint cheap!

 

Ok, so what exactly are your mpg numbers? How long have you been checking?

You could certainly pick a better air filter, but that one won't really hurt you. Are you saying you haven't changed the ATF in 60,000 miles? I would definitely do that regardless of whether it helps your mpg rating as 6th gen automatics are NOT very forgiving.

BTW, don't worry about the fuel filter as you can't actually access it. It was designed into the fuel tank with the pump, as Honda doesn't believe it is a necessary maintenance item anymore (and they have been correct 99.9% of the time on this).

 

Ok there's not check engine...and it's an automatic transmission.

I'm checking my gaz mileage for a year now.

Before :
City:29.4 MPG
HW:36.19 MPG

Now:
City: 20.45 MPG
HW:27.67 MPG

And the problem suddenly happen...what about the pre-cat O2 sensor???

thanks all!

 

The problem I have with it being the o2 sensor is that there is no check engine light (as there SHOULD be for an o2 sensor issue).

HOWEVER, there have been cases where people have found their o2 sensor(s) to be causing problems and they threw no corresponding code. So it can be hard to tell.

Have you investigated your injectors at all? You might want to try throwing in some injector cleaner (get the good stuff: Lucas, Techron, Redline, whatever your preference) and look for improvement if you haven't.

 

Try Seafoaming your car in addition to changing the tranny fluid. Though for the Seafoam I would only use 1/3 through the brake booster line and the remaining 2/3 in the gas tank.

 

I wouldnt use Seafoam, too many ppl complain about it. Try using Engine Restore Upper Cylinder Lube. It's a really good injector cleaner as well as over all cleaner. Its in a clear red bottle and should be at almost every parts house. I know for sure they sell it at Advanced. I wouldnt be tryin so hard to sell ya on it but it amazed the crap out of me. I used to use both Lucas and Seafoam but this just seems to work better.

 

Its probably that BP gas you keep putting in your car.

 

I haven't really heard any complaints about Seafoam other than if you put it in your oil and dont change it within 5 miles! Hence why I only use it in the gas and brake booster.

 

I've wondered whether this worked well or not. Been meaning to ask around.

Same here. Only other complaint I've heard is if your pushing higher mileage on original gaskets it's risky to use.

Something I'll add, my car has only been seafoamed once and it did nothing to positively affect gas mileage. This was at around 185,000 miles. Just throwing in my experience.

 

Another thing that you might wanna try is Berryman's B-12 Chemtool. Just dont get it on a cut or in ur eyes, cuz that stuff burrrrns!!! lol But man you always gotta b careful w/ what you use in ur car. Alot of that stuff was tested on engines w/ less than 100k miles. I know every one loves to talk bout Slick 50. I put that in my 95 Civ w/ ove 150k on it, n three days later spun a bearing... So ya just gotta be careful w/ what you use, use what u feel comfortable w/. But just my opinion, try the Engine Restore. You should start to notice a difference w/ in 15 miles of highway or hard city driving. Just pour in the whole to 10 gal of fuel n ur good to go. Good luck man.

 

Seafoam wouldn't still be around if it didn't work or if it caused problems. As far as gaskets, any high solvent additive will eat them. I have also heard it can eat away at fuel lines if you leave it in too long and don't drive enough to get it out of the fuel system relatively soon. Other than that, Ive heard nothing but good things about it

 

With product marketing these days, I tend to go against that train of thought (Z-Max anyone?).

However, I would agree with you that Seafoam itself doesn't create many issues. More often than not it's user error if there are problems.

 

Very true but I figure if it caused major problems it wouldn't be used as often.

 

Agreed.

OP, any updates?

 

Not sure if this pertains to the subject but I had a CEL throwing a P0420 code. Autoparts guy said bank one sensor. I was going to wait until the weekend to change it. Drove 2 days and code cleared and I was averaging (V6) 22mpg and last tank was 24mpg. Beats me as to what happened but I'll check this tank when I fill up again. I would agree with the fuel injector cleaner as to your dilemma.

 

Has your car recently overheated? How do your plugs look now? Sometimes your plugs can tell a lot. Change your oil. I would go back over all the parts you've put on your car and make sure they're all correct for your car. You can also make a mark on your spark plug socket and face the spark plugs to the mark and when you put your plugs on, face the plug mark to the intake manifold.