Hello,
I'm new to the forum and new to hybrids (driving, but not the technology -- was translating Japanese documents about them 10 years before they hit the road).
I just purchased a used 2004 HCH 1 MT, after very careful research as to the best high mileage car for my application (mountainous area, most driving around 45 - 55 mph, compared with VW Beetle diesel, Prius, etc.). I decided on the HCH1 MT as most cost effective given budget, etc. Figured I would save about $1500 per year in fuel based on 45 mpg, amount of driving (my wife's commute) and gas at $3.55 over her Subaru Outback. So far we are averaging well over 50 mpg (according to the meter). I get about 56 on the highway, up to 58 on the paved secondary roads (excluding over the mountain trips, about 50 on these). This is with basically our normal driving techniques (always economical). So far we are absolutely delighted.
I have a few questions. Pardon the long first post.
1. Tires. The car has one of the original type Bridgestones, one other Bridgestone and two other tires (of one make but my wife has the car, so I can't look). All right sized in good shape, but mismatched. Would it be an advantage to change tires or just let these run?
2. Economy setting. I at first thought that the car should always be set to shut the engine down at stop signs, etc., but I wonder what the collective wisdom is on this. If you are only making momentary pauses (stop signs in no traffic, stopping to park, etc. Any thoughts appreciated?
3. Acceleration: following the advice I have gleaned from various sites, I have opted for a moderate acceleration, enough to get the assist going without going crazy. What are your thoughts?
4. Steep inclines: how would you approach steep inclines? So far I have been keeping the gear as high as possible and using as much assist as possible without being ridiculous. Any thoughts on the balance? (This process is a little counterintuitive to a long-time MT driver, and the instinct is to lower gears. However, the hybrid seems to have this second wind when you kick in the assist. I assume that helps mileage. Right/wrong?)
5. Oil changes: I assume every 5K is in order in my application. What do others think?

 

i have an 05 MT, and i can tell you what i have learned with it. by the way, you are already going great with your fuel economy, and the MT is truly great for that.

1. while i am not sure the effect of mix and match tires are, one thing you can do is inflate to the suggested number on the sidewall of the tires. underinflated tires cause both wear on the tires and can slow down the car. if you car came with bridgestone 381s, they are a great low rolling resistant tire, but hard to find since they have been discontinued.

2.i would suggest leaving economy on. i have almost 80,000 miles on mine, and i use the autostop when ever the car will do it. i have seen no problems, and haven't really heard of any. you will probably lose the effect in the winter, since the car doesn't warm up as soon, but you will be ok with it on.

3. easy acceleration is the best way, trying not to get it over 1500-2000RPM. you really should avoid using the assist if at all possible, since it will work, but will cost you FE trying to charge it back up later.

4. on a steep incline, whenever possible, you should try to keep your pressure on the pedal as consistent as possible, called "driving with load." it will slow you down, but you can make it back up by coasting down the other side. i would keep it in a lower gear, and again, try to use as little assist as possible. sounds counter intuitive, but that really works the best.

5. i run 0W20 synthetic, and change oil every 15,000. what weight is in the car now?

 

Thank you for the useful hints.
I assume that the oil is Honda 0W20, but am not 100% sure. I bought the car from an Acura dealer and it was gone over and serviced by their Honda shop, including oil change, etc. before I purchased it. It has 78K miles on it -- just a couple thousand left on the hybrid parts warranty. I notice a lot of people talking about using synthetic oil. I've never used it. What are the advantages?

I intend to keep the tires up to mark on inflation. All indicators from users point to that as a real important factor.

I get the feeling from your post that using the electric as little as possible is the real key to FE. Is that a reasonable assumption?

 

the oil i use is mobil synthetic. it seems to be working very well, and you can go a lot longer between changes. my oil change place didn't carry it at first, but now they do.

78,000 on an 04 isn't bad, that's about what i have on my 05. i had 45 mile drive to work for almost 7 years, and that really put the miles on. but hondas go like the energizer bunny. my ex has my old 93 civic LX and i think it's on 200,000.

so far from all indications there have rarely been battery problems with the IMA battery, but keeping the assist as high as possible does save it, and also helps with your FE.

sounds like you have a good handle on things, and should really enjoy some good numbers with the car.

 

1) Tires

For maximum fuel economy it would be best to have all 4 wheels outfitted with the special rolling resistance tires, however this is not the "greenest" option. The greenest thing to do would be to use the tires you have. The gas savings by switching will not be that great.

2) I leave autostop off as a rule, preferring to FAS well before autostop would kick in. Every once in a great while the car will AS when you don't want it to and will refuse to get going again for a couple of seconds, I'd rather not deal with that. If you decide to FAS please be careful as it is not an entirely legal or safe thing to do.

3) Acceleration is a hotly debated topic. Clearly neither too fast (tires spitting gravel), nor too slow (so slow you never hit top gear) is best. The answer is somewhere in the mid range. Lower-middle is generally regarded as best but a case could be made for giving the car a little more gas as well.....Do as you like, it is your car after all.

4) Depending on the steepness and length of grade it seems to be best to build up a little speed in top gear before you hit the incline. Use the tallest gear you can use without using too much assist. You don't need to avoid assist all together, just minimize the use of assist. This is best for FE and the life of the traction pack.

You don't want to be in top gear, with an empty pack, halfway up a hill. Down shifting is a much better option on long grueling grades. You should be able to pop over small hills without the need to down shift.