To a certain extent I can control the SOC. This however is somewhat limited by terrain and environmental conditions among other factors. On level terrain in moderate temps I can usually keep the SOC above 3/4 but introduce long hills, extreme heat/cold or even a stiff headwind and all bets are off. I also find letting the car sit just overnight, let alone for long periods, will just about guarantee me a recal first thing.

I've learned to live with the frequents recals and loss of IMA assist. They usually happen at the least opportune times, climbing and on ramps, so I have just learned to suck it in, drop it into 3rd (or sometimes even 2nd) and get lousy MPG's until I get over the hill or up to speed. I can live with getting 30 MPG 5% of the time to get 50+ MPG the other 95% of the time.

As for mods to keep the car going after the 12V stops charging nothing really seems worth the trouble to me. We have to let them go sometime after all.

Although one possibility would be to just charge the 12V manually/daily and use the car as a local commuter vehicle, errand runner or field car, at least in daylight hours and good weather...

 

Thanks. I agree we have to give them up sooner or later. I'm just crossing my fingers 12V battery charging failure will not happen for a while and we can get some service miles out of the vehicle. Seeing reports of Civics going into the 200's or more tells me there are many miles in 95% of the car and to "junk" it due to the inability to charge the 12V... well. Worst case maybe will be to replace the 144V battery or DC-DC converter (both expensive repairs) and a tradeoff when/if it happens.

Recharging the 12V daily (if it isn't getting any charge via the IMA/144V/DC-DC converter path) might really limit the use, either in time or miles. Any idea what the limit might be? I'm sure it depends on the condition of the 12V and its ability to hold a charge, but also on the "needs" of the car (lights, etc.) and the 1.3L for injectors, spark, etc. Some idea would be good in case the failure occurs (indicated by the 12V light coming on) and you want to know how long you might have before you are stranded! I assume it is like an alternator going out on a regular car.

 

Yes I did do 1003 miles on a single tank, it is my personal achievement which took 3 years of dedicated self-training. GH was mostly populated by hypermilers back in 2004-2006 and I had some good company from the best of the best.

Certain conditions existed back then which isn't available today so I could not duplicate it. Probably the biggest contributors to it was:

* 50 mile commute to work, about half freeway and half residential highways
* I worked off hours, my evening commute from 2-3am with zero traffic
* I live in Georgia. Hot humid summers and decent winters.
* I drove into the city while most everyone was going out of the city.
* Only used AC very rarely- and when I did it was only short burst. I relied on a Coleman cooler of ice & water and a cloth to keep from overheating.

I used most of the extreme hypermiling tricks others use (Engine off coasting etc) however my main rules was safety and not to become an unreasonable bother on the road. I never close-in drafted trucks.

I used extremist obsessive measures to get my record, way beyond anything anyone would consider normal and into the ridiculous. But I also learned a good lesson about many things regarding fuel conservation and I still apply some of those things in moderation today.

It may not sound like it, but my few hypermiling years was the most enjoyable and satisfying time spent in an automobile in my 36 years of driving.