93 Honda Civic VX horrible fuel economy

[imzjustplayin]

Originally Posted by pgfpro

Sorry. I have been following to many forums lately.

After looking at your log your car seems to be doing great! I think the drop in MPG recently is all to do with the dreaded winter months.

My wife's Honda and Sons Honda are both put away for the winter to protect the new paint jobs, but I do know when we used to drive them during the winter months the mileage sucked.

I was thinking the same thing, however if this guy is going to extreme lengths like EOC and whatnot, then I can see why he'd be annoyed with the fuel economy numbers he's getting. Everyone on this forum should be capable of getting the vehicle's "Old" (1985) EPA fuel economy numbers and for the more dedicated ones the original (1975) EPA fuel economy numbers, AKA CAFE numbers, all without doing things like disabling or removing hardware nor using EOC. For those older CAFE numbers, check out this page:http://fueleconomy.gov/feg/download.shtml
It's in the left hand column and the older format files only need to be opened in wordpad in order to be viewed.

[benfrogg]

I had the car off the ground for two days while I installed a belly pan. (only had enough coroplast for 2/3 or it) I decided to also check rolling resistance of the brakes, drive train, etc. Rears spin freely and continue to rotate 1-2 times after spinning.
Front wheels are another story. I can turn them by hand, but they don't keep spinning after I stop pushing them. I can't tell if it is brakes dragging or very cold oil in the transmission (garage is only heated to 55df when I'm doing the work; I use a 40k btu propane heater and it cools off quickly after it has shut down) or both.
What could be the cause if it is brakes? Could temperature cause those pads to grab a little more?

I replaced both front calipers this last summer. I bled every wheel twice starting at the furthest from the MC and the fluid was very clean by the time I was done. What could be causing them to bind up? They both appear even in their difficulty to spin. That's why I was thinking just cold trans fluid. (mobil 1 synthetic motor oil per factory specs) Is that possible?

What about wheel bearings? It seems odd that they would be so even like that if it were wheel bearings but I don't know.


Yes, as ************* said, it is frustrating not to be able to hold even new EPA estimates before making any major changes other than driving technique. That's why I'm still after my, "smoking gun," that will net me 5 more mpg's all the time.
The MPGUINO has been helping a lot. The new gaslog data will show that.
I'll update my gaslog tomorrow after the next fill up.

Also, the block heater will help a lot, I'm sure.
Thanks
B

[benfrogg]

Just found this:
http://geometroforum.com/topic/3808281/1/
I assembled my new calipers/pads with PLENTY of caliper type grease. It only takes one squeeky brake after reassembly to make one do this.

I'm going to tear them down tomorrow and clean all the grease off of them. Maybe that'll make a change? If I have time I'll post a video of before and after!

Any other reasons?
Thanks
B

[pgfpro]

I think both our Hondas do the same thing on the front wheels as far as rotating by hand goes.

I always do a coast test with the car warmed up after driving a few miles. I use the same section of road and keep in mind the wind speed during the time of test. I like to use 40mph as my starting point. With new Honda bearings installed I had a 28% increase.

Is you car easy to push on level ground?

[benfrogg]

It is relatively easy. In the garage, I can move it pretty readily.

When you did your last brake job, did you use a grease behind the pads?

Did you do all four wheels with new honda bearings or just the rears? I assume the fronts have to be replaced with the whole hub assembly?
B

[theholycow]

For the same reason I wouldn't expect wheel bearings to be even, I also wouldn't expect sticky brake calipers to be even. I'd say it's in the transmission.

[GasSavers_Erik]

Do you have 10w-30 in the transmission?

Do the spin test right after a long drive (when the trans oil is warm) and see how it does. It would take a few hours of 55 degree heat to get the trans and oil heated up to that temp.

[benfrogg]

I'm going to see how gooped up the calipers are today, just for grins. I recall using a product for anti-squeel and I'll dig the bottle out later. It may not be the right stuff. It was specific to lubing the caliper bolts, but may not be right for the pads. I don't recall if there were shims or not involved, but if there were, I would have coated both sides which is a no-no.

It's probably the transmission as HC pointed out. I'll try the test again after a long drive and see what happens. I have a 30 mile hike to make today. I'll also know at the end of that if my heat shields are sufficient to keep the exhaust from melting the coroplast paneling.

I don't remember if it was 10w30 or not. It was synthetic motor oil, that's all I remember. Is 10w30 what honda recommends or is that what you suggest? I would have done what honda said the first time. I'm open to suggestions now. I was wondering about syncromesh for the tranny? I don't know if they are compatible or not.

I'll give an update!
B

[benfrogg]

Turns out I used the permatex brand caliper grease. It is the right stuff. I used a clamp to loosen the caliper. It is definitely the transmission providing the resistance. I believe it was filled with 10w30 mobil 1 over the summer. (may have been 10w40)
Anyway, another good reason to use the block heater! (maybe get a magnetic trans warmer?)
B

[GasSavers_Erik]

10w-30 should be correct unless the car was being driven in a really hot climate.

Better not spend any money on the magnetic trans warmer- your trans case is almost certainly aluminum