93 Honda Civic VX horrible fuel economy

[GasSavers_Erik]

PS- here's a link to a 92 civic factory manual if you don't already have access to one: http://www.redpepperracing.com/technical/main.php

[benfrogg]

Thanks for the manual. I have one already but it is a pdf so it's good to have a couple of sources.

I'm going to do some seafoam tomorrow. I did it once before but didn't shut the car down and wait like people say to. Guess I should read the bottle next time. I'm hoping to see some results through the process.
Also, I plan to pull the brand new 02 and put the old one back in for the test. No sense risking a brand new $200 part.
Oh and I won't put it in the oil. No thanks.
B

[imzjustplayin]

Originally Posted by benfrogg

Thanks for the manual. I have one already but it is a pdf so it's good to have a couple of sources.

I'm going to do some seafoam tomorrow. I did it once before but didn't shut the car down and wait like people say to. Guess I should read the bottle next time. I'm hoping to see some results through the process.
Also, I plan to pull the brand new 02 and put the old one back in for the test. No sense risking a brand new $200 part.
Oh and I won't put it in the oil. No thanks.
B

why have either in there? **** if you're really concerned about protecting the catalytic converter, you'd just put on some headers there and remove all sensitive o2 sensors so they don't get damaged... that's assuming you care at all..

[benfrogg]

I suppose I could just leave the 02 hole empty. Wouldn't hurt anything. Might let some of that crap exit there instead into the cat.
On the other hand, I can leave the old useless 02 in the hole while I test drive afterward. No harm there, I don't think?

I could pull the cat, I suppose. I just figure it would be absurdly loud run at full throttle immediately afterward. It would also mean i couldn't take it out for a "spirited" drive shortly after doing the cleaning.

I've heard primarily good things about seafoam. I've personally used it (although never apparently correctly) and had friends that have used it (correctly) with no ill-effects.
Most of the negative information I've heard about it is from tuners and racers. Most of what they said refers to people who use it on a regular basis. In that scenario, I could see potential engine harm. I plan to do an oil change shortly thereafter.
The only other issue is that of what it might do to the cat. The product itself is liquid; the stuff that frees up may be solid. That could potentially clog the cat, I suppose. I find it hard to believe their product could do damage and still have the reputation it does. Most old timers have been using it for years. I guess I'm willing to take the risk for a one time deal. The spare motor I'm picking up saturday has a cat on it.

I'm open to suggestions/comments/experience with the product if anyone has some.
Thanks
Ben

[benfrogg]

Turns out I had an old old 02 from her car's last replacement. It was definitely dead. I put it in and got the car warm. I ran 1/3 in through the brake booster line. I let it sit about 12 minutes and then took off for a "spirited" drive. The smoke show as pretty intense. I rounded the block and when I came back, the whole street was a haze.
After about 15 minutes of driving, there was no more smoke.
I repeated the process with 1/3 more of the bottle. Still smokey, but it cleared up more quickly. That alone seems to add to the argument that what was burning up was not the seafoam but the crap in the car.

Immediate conclusions:
It does idle better. No question about it. I have the idle set to just at the lowest needle above 0. It looks like it is at the 250rpm mark, but I hear tell it is at the 500rpm mark. Anyway, it's smoother. That is no placebo effect.

As for driving it, I won't know until tomorrow. I'm taking a long drive tonight and I'll report back.

I also change the oil to mobil 1 0w20. It's been cold and at these temps it cant hurt.

B

[imzjustplayin]

any update on whether grounding the exhaust manifold and other such changes have improved your fuel economy?

[benfrogg]

Yes-
I've got a fillup to do this week. (I fill the tank a lot less because I get 600 miles between fillups... also, work has slowed a bit so less driving) According to the gauge, I'm at 59.5mpg for this tank.
Definite improvement between fuel filter/grounding/ a few other things. In the automotive tech section I talked about re-adjusting Toe properly in my garage; that added to the higher mpg's.

We'll see how close the gauge is to this tank. Last tank it was 1.2% lower than the gauge, so we'll see. I had a tank that was way off from the gauge a while back, but that was due to expansion/contraction of fuel based on temperature. I'm going to make a serious effort to only fillup after a longish drive and when the tank is after 575 miles. (600 miles leaves me with a .5ish gallons left) That will increase my accuracy.

By the way, I forgot to mention- Maine has only 10% ethanol fuel no matter where you go. All of these numbers are on E10 fuel.
The winter fuel around here is really a very different mix. A local insight owner complained of going from 60mpg tanks to 40mpg tanks. However, there are a lot of other factors there. (cold starts, idling, driving in snow, etc)

Thanks for inquiring, I'll post more updates as tanks follow.
B

[benfrogg]

Single best trip since buying the MPGUINO and keeping track of specific trips:
31.07miles 65% highway.
69.33mpg on the gauge.

The trip there was a record until that trip;
36.82 miles 60% highway (different route home than there)
68.06mpg

Latest tank actual mpg was 58mpg (see gaslog)

Now to get that 90 day average up!
Looks like things are improving due to the mods/repairs. I'm happy so far, looking forward to less 10df days.

[Fuel Miser]

Impressive, congratulations on your success. I motion this thread be renamed "93 Honda Civic VX, wonderful fuel economy".

[benfrogg]

Indeed, it is probably time for a rename... although it has been a saga from bad to good. Maybe something like; "93 Civic VX from bad to great FE"

Anyway, thanks all for tuning in. I'll post some updates here as things get better (hopefully) over the spring.
B