Well I finally went out and did it, bought a used 2005 HCH 5 speed. Got a good deal on the car because it had high mileage, 70K. It is Honda Certified and while that gave my 12k miles of warrenty, I opted for the extended which takes me to 100k bumper to bumper. I checked the trip odometers and found one with 9,000 miles on it and only 40mpg. Which had me a little worried but figure the former owner might have had a lead foot. I immediately took it from the dealership and upped the tires to 42psi all around. Max sidewall is 44 and they were at the normal 32psi. It had a half a tank of unknown gas when I took it off the lot and I filled it up to start a new record of mpg. I live in northwest Pennsylvania and we have a lot of hills and back roads in my rural area with very little city driving. The first couple days I just drove it back and forth to work, 60 miles round trip on rural state hwy, and was seeing 47.7 mpg. On my first day off I took if for a 200 mile run in a big square on a mix of back hwys and interstate and then filled back up with the tank only being down about halfway. My calculated mpg was only 42.7 mpg compared to the 47.7 it was showing, but still better than what the previous driver had been averaging so I was encouraged since I am just stating to learn how to drive it.

I did have a check engine light come on and took it immediately to the local Honda Dealership, different from where I purchased it, who informed me that an O2 sensor needs replacing and they put it on order and should be installed later this week. Code P1130 & P0139.

They also updated the software 125517 ECM/PCM. All covered under the warranty.

They also told me something that the dealer I purchased it from failed to mention and was not on the carfax either. The car should have never been Honda Certified because the right front fender does not have the VIN on it indicating that it had been in a wreck and replaced. I of course became very concerned at that point about the warranty and their service mgr assured me that while their dealership would not have certified it, now that it was certified, Honda would not go back on that and they double checked the information on the certification and warranty.

I am now on my second tank of gas and seeing 49.9 mpg on my regular commute for the first 300 miles of this tank. I am doing things like feathering back on the upside of hills and if the batteries are showing at least 1/2 full on the gauge I put the clutch in and let her coast down the other side. Man can this car coast. I was able to go almost 2 miles coasting at no less than 45mph going up & down increasingly smaller hills along the way. I an going to let this tank get down to when the light comes on before refueling and finding out how it is really doing.

I know I have been very long winded and do apologize for that, but I am just very excited about this car. I do have a couple of questions for you all, if you don't mind.

I always see info about how to get the most mpg with the HCH-2 or the HCH with CVT but rarely see any info on the HCH with manual transmission. Would love to get some of you 5 speed owners advice?

Also does anyone think I should go back to the dealership or Honda itself about the car having been previously wrecked and still being certified by the selling dealership? Thing that really irked me is I even asked the manager there if there was anything about the car I needed to know, that was not covered on the carfax and he said Oh no, there is nothing. It wouldn't have stopped me from buying it because the price was right but knowing what I know now, I would never buy from that dealership again.

Thanks for any and all help/advice.

 

I too have a HCH 5-spd and am quite pleased with it. As you noted, there can be discrepancies between the displayed and actual mpg readings. I guess the flow meter, which measures fuel volume over time increments, has a +/- factor. The most accurate results will be obtained by dividing miles driven (you can calibrate your odometer too) by the total quantity pumped in. Going fillup to fillup only adds the variability of just how full the tank is when the auto shutoff stops the pump.

The question of coasting is interesting, but not something I've really experimented with much. If the motor is not running at all, as in auto shutoff mode, then your coasting is producing infinite mpg. It's more likely that it is actually still idling, so you're not quite reaching infinity. The question remains (and I don't have the answer on this one), do the fuel injectors stop injecting fuel when there is no throttle and the car is coasting down hill but still in gear?

The reason this might be a factor in your efforts to maximize your fuel efficiency is that if fuel is not being consumed while coasting in gear, and all you are losing is the energy it takes to spin the motor and transmission gears under no load, you might do better leaving it in gear and letting the battery charge right up. There's a lot of "free" energy to claim by regeneration. And you also won't be wearing out your brake pads converting that free energy into heat instead of electricity.

I have found that if my battery is even a little below half that the ECU will force a slight charging state, even under the lightest of throttle loads, where with a more fully charged battery in the same conditions there would not be any forced charging. Of course, driving AND charging at the same time will use more energy (more gas), so if you were to end up needing to recharge while driving because you pass up the opportunity to recharge with the downhill energy you might actually end up hurting your fuel efficiency.

That said, if your battery is nearly full and you're sure you're not going to need it all on the next uphill - Coast away! In fact, I've noticed that when my battery is fully charged the regeneration feature is disabled, and the brakes have to do all the work slowing you down.

I'm not a fanatic or hyper-miler, but I do enjoy trying to understand more completely how the HCH creates and recycles the energy it extracts from the gas I put in the tank. I simply try to keep the engine in it's most efficient RPM and load range (not too fast or too slow, not too heavy or too light on the gas) and then try to collect (recycle) as much of that energy through the regeneration feature.

I hope you enjoy your 2005 HCH as much as I do mine.

P.S. Oh, and I wouldn't worry about the replaced fender too much. It might not have even been involved in a real "accident". There are lots of trees and rocks around my driveway, and they sometimes move to unexpected places when I'm not looking.

 

Well I didn't want to leave this post as is because it upon rereading it I think it could give some people the wrong idea about what I think of this car, so here is an update.

As for my problem with the dealership, I contacted Honda of America and they informed me that while there are dealerships that would not have Honda Certified the vehicle, that there is no rule against it in the certification process. They did agree that the dealership should have informed me of them finding that it had been in a previous fender bender. The Honda rep did try to explain that with the accident not having been on the Carfax, that the dealer might not have know it and couldn't have informed me of what they didn't know. My response to that was that the dealer I took the car to knew within 15 minutes of looking at the vehicle so it was rather obvious that one fender didn't have the VIN code on it, indicating an accident of some kind. She was very responsive about it but of course trying to cover for the original dealership as neither of us really had any proof that they knew or didn't . She did ask me what I was looking for and how HOA could help. I told I just wanted it on the record that I had brought this issue up in case something comes up later in regards to that accident and that both the Honda certification and extended warranty were in place to stay. She assured me that my concerns were now in my customer account and that the vehicle will have no problems with warranty service.

Now for the vehicle itself, it is in great shape and using some of the advice that I was given over at cleanmpg.com and the software update from Honda my second tank of gas was at 50.7 calculated and 50.7 from the FCD. Have since then had the 3 O2 sensors replaced, covered by warranty, and on this 3rd tank, which I am 400 miles into, the FCD is reading at 54.5. This is all back highway driving, very rural with lots of curves, steep inclines, and an almost never ending changing terrain. Have a trip in the near future of 2200 miles of interstate driving over 4 days, so should then get some stats on what this baby can do open highway. I am very pleased with the vehicle so far and see that as my driving habits are changing the mpg is climbing.

Overall am very pleased with the purchase and am actually glad I got the HCH over the HCH-II as I love the stick and some of the things that you can do with it.

Happy Trails!

 

Hi, this may answer the highlighted part of your post ...........

'The i-DSI petrol engine uses three-stage i-VTEC valve control to achieve a combination of responsive driving and fuel economy. The valves are controlled by three hydraulic pathways, which couple and uncouple five rocker arm assemblies. During deceleration in this idle time combustion in all four cylinders is stopped and each pot is sealed shut. This means the engine is not working as hard to pump fuel or air, so it’s immediately more efficient.'

Somehow, when coasting, all the valves shut. The pistons 'freewheel' and no fuel is used. As one piston is descending from compression, another is rising into compression, hence the 'freewheel'. And as no valves are open, no fuel is used.

I bought a HCH 2005 with 13000 miles in February. With careful driving I'm currently returning 57 m.p.g. ( that's UK gallons ) It's a fantastic car and I would recommend one to anyone.