Decrease in mpg since oil/filter change

[uRabbit]

Sep 5 @ 30,095 mi performed oil and oil filter change.

Tank just before got 39.3mpg. Since then, I have filled up eight times and never put less than 8.92 gallons in, filling up all the way every time.

I have not changed driving style at all. No Jack-rabbit starts. Never exceeding speed limit (max 65). Shifting @ 2200rpm. Using downshift engine breaking at all times as well. Also using cruise control whenever possible.

However, I have noticed the smell of fuel around my car and sometimes inside it. I don't smell it every day or every trip on a day I do smell it.*

Before oil/filter change, I haven't gotten over 36.5.*

[cab0053]

how much oil did you put in?

[uRabbit]

Whatever the recommended was. I believe 4.5 quarts? Don't remember exactly. I just looked in the owners manual and put that much in. Dad said to put more in. Brother said less. Haha I put the suggested.

[Antpwny]

Synthetic or Regular Dino? Weight?

[uRabbit]

Oh ya. Synthetic 5w20. The recommended weight if my off-the-top-of-my-head numbers are incorrect.

Went with synthetic, as I've already put 3k miles on since then.

[cab0053]

Really? I thought it was 3.8 qts... oh well

[shazaam]

yea it's 3.8q lol. coulda used a dif viscosity last time. cruise kills mpg over a steady foot btw. same gas station/fuel type...

[uRabbit]

3.8 sounds better. Haha. Believe me, I stuck to the recommended.

A steady foot, eh? I've read and heard that there is more pedal fluttering by the human foot. Maybe it's just the fact that I've run the defroster on setting 2 at 3/4 heat most days, since the weather has gotten colder.

Edit: one of many articles providing tips http://www.edmunds.com/advice/fuelec...2/article.html

[gwh]

with defrost on,a/c is on automatically. could change mpg by a small amount.

[uRabbit]

Last tank was 32.4mpg. I must have a gas leak or something. I think the smell of fuel is coming from my foot compartment. That's where it is strongest, at least.

[shazaam]

can check for an exhaust leak...usually can hear it .

[uRabbit]

Well I'm not exactly in-tune with that, so how does one go about finding that?

32mpg last fill up. >.<

I am beginning to worry immensely about this issue. If my mileage can drop that much in only a few tanks of gas, then it must be a big leak... I don't have hundreds of dollars for repairs nor am I under warranty. What parts do I need to check and what do I need to look for?

[theFITMASTER]

Originally Posted by gwh

with defrost on,a/c is on automatically. could change mpg by a small amount.

best mod is to disable that feature!!!!! search for it

[Vash]

and your checking the dip stick as well? normal levels of oil still?

Oil is a petroleum so when you overfill it will dump into the cylinders and get burned up, which may cause you to smell it from the exhaust. It will smell like gas.

but last tank was 32.. thats a huge drop from 39

[uRabbit]

Yes I have checked oil. It is clean and at half (which is about right, considering the mileage since last oil change).

I am having the dealership take a look at it on Wednesday. I am almost to 36k miles tho. >.< And the previous owner put some modifications in it, so I'm hoping that the problem is not with any of that. Only mods I can see are blue hoses near the front.

I am thinking the problem is in the engine bay somewhere. No exhaust sound or anything noticeable with the exhaust.

[Daemione]

Originally Posted by uRabbit

However, I have noticed the smell of fuel around my car and sometimes inside it. I don't smell it every day or every trip on a day I do smell it.*

The weather is getting colder, and it's also possible that gas stations are starting to switch to winter blends of gasoline. Both of those conditions result in poorer mpg . . . As for the smell, I'll be honest - my first impulse is to think you're imagining things. I know firsthand how easy it is to start noticing unrelated (or normal) things you never noticed before when you're troubleshooting something.

Originally Posted by uRabbit

Shifting @ 2200rpm.

Just a sidenote - this practice may not be helping as much as you might think. The Fit really doesn't make much (any) power down there, so asking it to accelerate from such a low rpm can really put a strain on the engine, resulting in poor mpg on acceleration. And even in steady state cruising, I get better mpg numbers @ 3k rpms than I do @ 2k.

That said, driving safely in my area means keeping up with traffic, so no lollygagging off of a stoplight for me. And merging safely onto a highway means goosing it pretty good. But even dealing with all that, I get 30+ mpg - 100% city driving.

[uRabbit]

Those are the RPM's at which the speeds are that the Honda manual suggests to shift at.

My suspicions were confirmed today by the local Honda dealer. There is fuel leaking out of the gas tank. They say their theory is that when the previous owner had his amp in the vehicle, he must have drilled thru to the fuel tank and punctured it. The hump in the middle of the foot area in the back seat area is sliced open and there is Duramat in there as well.

So they quoted me $657 for the job.

So I guess I'm going to be looking to purchase a gas tank and find a cheaper mechanic to do it. Problem is, I have no clue where to get one. Nor do I have money for one. Yay. Joys of owning a previously owned car.

[uRabbit]

What gets me tho, is:
1) Why did it get great gas mileage before?
2) Why has it steadily gotten worse?

Cause if the previous owner flubbed up by drilling holes in the gas tank, then it would have been noticeable on the second fill up... I'm just scared to find out exactly cause I don't have $300 for the labour to make sure.

I'm thinking they're just dodging me cause the car is out of warranty in 800 miles...

[Daemione]

Originally Posted by uRabbit

Those are the RPM's at which the speeds are that the Honda manual suggests to shift at.

My manual has recommended shift speeds of 15mph into 2nd, 27mph into 3rd, 34mph into 4th, and 53mph into 5th. That works out to 3300rpms for the first two shifts, the shift into 4th @ 2800rpms, and into 5th at roughly 2500.

But like I said, I regularly shift @ 4000rpms going from stoplight to stoplight. Between 3k & 4k is where I find the best compromise of mpg & power for my commute. And unless you live somewhere where there's zero chance of encountering an incline, I don't know how anyone can live in 5th gear @ 2500 rpms. The car will struggle to make it up the tiniest grade, and mpg plummets every time. For parkway cruising near me (the Merritt parkway, if anyone knows it), I have to keep it in 4th gear up to about 65mph. GE's might do better w/ the iVTEC engine.

Originally Posted by uRabbit

My suspicions were confirmed today by the local Honda dealer. There is fuel leaking out of the gas tank.

Blegh, that totally sucks.

Originally Posted by uRabbit

What gets me tho, is:
1) Why did it get great gas mileage before?
2) Why has it steadily gotten worse?

How long have you owned the car? In other words, did you buy it the beginning of the summer? Again, my thought is that if it's your first time driving it in cooler weather . . .

Originally Posted by uRabbit

I'm thinking they're just dodging me cause the car is out of warranty in 800 miles...

If it does turn out to be a significant problem that your fuel leak doesn't solve, you've got the original claim in before the warranty cut-off. You should be okay, just keep your documentation so you can make a fuss if needed.

[Btrthnezr3]

Maybe jacking it up for the oil change caused a little body shift and thus made the leak apparent? Just throwin it out there...