Wow, I've created a monster! I sorta ignored the post during the holidays...serves me right!

Anyway, to address a few queries:

Latest MPG is 26.3 This with the new Oxygen sensor and spark plugs.

I bought this one after it sat neglected for a year, I got it cheap and went to town.
From the first round of repairs in Feb 07it has:

New fuel tank, new pump, new strainer.
New timing belt, balance shaft belt, new oil seals, cogs looked great. I always check the idler/tensioner pulleys too, they were fine.
New cap and rotor, new coil. - Interesting note, the coil died ten minutes after I started it up with the new timing belt. Just dumb luck. Don't think that didn't drive me crazy for a few minutes. Is the belt ok?! WTF?!
Valves adjusted to spec - 0.012" on exhaust and 0.010" intake - whatever was on the VECI decal under the hood. I used to adjust the valves on my motorcycle so it's a familiar process to me.

Fast forward to today:

Tires are the same OE size, fronts match and rears match, and they're fairly new. They are both over 300 UTGQ. Still at 31 psi.

No pulling or alignment issues. No abnormal treadwear.

Just yesterday, I checked compression. 190-195psi on every cylinder, warm.I even forgot to pin the throttle open during cranking. I was a little shocked that it was that good.

My drive to work is 13 miles, one way, so26 miles daily. I live in SC, so I don't do a warmup. Ten seconds after startup the car is backing out the drive. It seems to average 20-27 degrees at the coldest time of the year, and almost always warmer during the day.

What's wrong withBosch? Surely it must be better than the original oxygen sensor.Either way,it didn't seem to affect the mileage much this last tank.

I researched top tier gasolines, and I've tried a fillup today with Shell 87. If I drive home a different way, I go right by the station.

Drummer1279:
The simple answerconcerning E85 is that flex fuel vehicles have a sensor to tell the PCM how much alcohol is in the tank. Timing andinjector pulse widthare adjusted accordingly. This is how people can fill with gasoline, than fill half a tank of E85, then more E85, then straight gasoline.The carcan measure the ratio of gasoline to alcohol. It isliterally a flexible fuel vehicle.

Your lawn mower will run on E85 if you upgrade the fuel line and enlarge the main jets 20%. Of course, this is a one way conversion on a carburetor.

 

Does your car warm up w/i first 5 minutes of your drive to approximately mid-range on the temp gauge? If not, a new thermostat may allow more rapid warmup to closed-loop operation and better avg. mileage.

good luck

 

Oh yeah - thermostat's new too. This car has no trouble getting up to operating temp in the morning. I have warm air from the heater at the same place in the commute everyday, like clockwork.

This thing really has me stumped. I feelsmart enough to have covered the normal stuff, I just wonder what I could haveoverlooked.

The temp runs about 1/3 of the way up on the gauge, and there's plenty of heat. It runs in the same place in the heat of summer or winter. The thermostat is rated 195 degrees. It seems to be plenty hot at the radiator hoses.

 

bosch = crap to me, but to you it might be gold. your call, you may have better experiences with it than me.

did you verify the purge control solenoid isn't stuck open?

have you check fuel pressure?(leaking injectors? fuel pressure regulator problem?)

 

As far as I know we don't have such 'dual fuel' vehicles here in Australia. Here 'dual fuel' means the engine can be run on either petrol or LPG. Our highest alcohol pump fuel is 10% alcohol.

 

It's a Honda, it's unlikely you'll find better OS than the OE unit, could be wrong. I had a Bosch electric drill once, not very good.

 

This is a genuine query. What is 87 gas ? Cant believe that is ROM or Octane number. Minimum ROM in UK is 95.

 

I was an industrial chemist for over thirty years before ascending to academics [ i.e. stopped doing a real job ] Best rule of thumb in calorific value is via the number of carbons in the molecule e.g. methanol 1, ethanol 2 and so on. Petrol is a mixture ranging approx from C10 to about C17. Derv is even higher. But the higher the C number , the more oxygen needed to give efficient burning. Is that any use ?

 

From what I can gather from below the equator, the Yanksmost commonly available fuel is only 87 octane rated. They appear to have other choices as wellincluding an 85% petrol / 15% ethanol blend rated at 110 octane (!!).

The low octane 87 fuel might be why a lot of cars meant for the US market seem to have quite low compression ratios, an example perhaps being the f22A6 CB7 Accord engine with I think about 8.8 CR, compared with the f22A9 CB7 Accord engine we got here in Australia with something like a 9.6 CR. Lowest nominal octane available here in Oz is in the low 90s, can't recall the exact number offhand.

 

I have had very goodservicefrom Bosch oxygen sensors and spark plugs. There are truly some crap oxygen sensors out there, but I consider Bosch, Denso and NGK to beexcellent quality.


Found this on an E85 web site about the sensing of alcohol mixed with the gasoline.

"E85 also requires a specially modified fuel injection system that can deliver a richer fuel mixture. Alcohol likes an air/fuel ratio of 9:1 compared to 14.7:1 for gasoline, so higher flow rate fuel injectors are required. The fuel system must also be equipped with a special fuel sensor that uses a dielectric measuring principle to determine the percentage of ethanol to gasoline (ethanol is more conductive than gasoline). The engine computer uses the fuel sensor's input to adjust fuel delivery and spark timing according to the concentration of alcohol in the gas"

academic,
In the US,auto fuel is classifiedby Pump Octane Number, writtenas "R+M/2" on the pumps. It's your RON(or ROM) averaged witha Motor Octane Number(MON), which is usually lower than the RON. They average the two rating numbers and stick that on the pump. So weend up with three choices, 87, 91 and 93. In the higher elevations you'll sometimes see 85 as well.


I guess I just need to get over it. My lingering question is this: How much of a drop are y'all seeing in mileage due to cold weather? Mebbe I just need to shut up and drive...