Ive been reading around and it seems that the HCHII may have a lean burn mode that can be activated to work in conjunction with the egr valve after gas. Has anyone experience doing this? Im not sure how to activate it, and I know the older insights have them.

Im at total odds with this car, the battery was just fine and didnt need reconditioning, though its only the dealer 6 amp hour batteries and not the 8 amp hour ones from bumblebee.

Im going to take it to the dealer when I get back home in a few weeks for a thorough inspection because its driving me crazy that I cant get decent mileage out of the thing.

if that proves futile, Im going to try my gamble with amsoil and pulstar plug combination, plus 51 psi LRR tires inflated to 51 psi. That combo up'd my alero to 35 mpg highway, but hard to say on the hchII. In all likely hood it was just the tire pressure and oil. Unless anyone can show me something refuting high pressure and the plugs. just from this video they give a bigger spark. I hear nothing but bad reviews from them, but I havent seen much else other then just opinions.

 

Found this,
it does appear to be a bigger spark, but does that ruin engine? Assuming it does that just leaves denso and ngk, so anyone know which runs better?

Update: Finally found someone who put it in there civic hybrid
http://www.8thcivic.com/forums/civic...yours-yet.html

Appearantly it doesnt help mpg.

 

Also found this,
https://www.greenhybrid.com/forums/f...latinum-22053/

Appearantly this car runs at high compression for 87 octane, and does better with iridium over platinum plugs?

 

Claims require evidence. Extraordinary claims require extraordinary evidence. That video proves NOTHING. The link you posted has a user that claims no difference.

The Honda is a highly optimized machine (there are under-body panels to reduce a tiny amount of drag for *** sake!). If Honda says to only use one of two Iridium plugs, that's what I use until someone demonstrates that a different product performs better IN THAT CAR. Who gives a **** if it's a stronger spark? Is that what it really needs? Why are there two plugs per cylinder? I don't know, other than to say that Honda designed it that way for a reason, and I bet it was mileage. If there was something better out there that improved mileage, they probably would have used it.

Honda has done nutty things with their combustion chambers from the 70s with the CVCC, and it's worked.

I'm not second guessing Honda. You shouldn't either because you buy into snake oils.

Here's some reading for you:

http://www.cleanmpg.com/community/in...threads/18185/

http://www.cleanmpg.com/community/in...threads/14295/

 

Well from this thread, it seems that they do nothing for honda civic hybrid's, and that at least was the evidence I was looking for.

http://www.8thcivic.com/forums/civic...yours-yet.html

That leaves just amsoil and high tire pressures for getting mpg up. There then again is the possibility of modifying the firmware for better mpg and maybe going back to the old firmware

But more importantly, How can one achieve lean burn mode activation?

Other older honda's have it, but not this one I guess. Do you know anything about accomplishing this? I get I made to much of a deal regarding the plugs, but lean burn mode would dramatically increase mpg, or at least be on par with the prius.

Update: Well im looking at the second article you gave, it doesnt do lean burn, but super highway mode? I still think lean burn is do able.

 

You will be the first person known to modify HCH2 firmware.

SAHM IS lean burn. I thought you would get that. Sorry.

Your understanding of lean burn is incomplete and your expectation is unrealistic. Do more research.

I have 3 Prius' (03, 07 & 08) and 3 Honda IMA (02 Insight, 05 Insight, 06 HCH2 and an HCH2 that I sold). The Prius have nothing on the civic hybrid when looking at conservative highway cruise.

You should probably sell this car. You will never get where you want to be because it's likely not possible without serious investment, and IIRC, you have a $1000 cap, which doesn't permit purchase of a new pack - that is likely the bulk of the issue.

Steve

 

I always assumed either the dealer could modify the firmware or there was some special aftermarket programing coder I could get ahold of Maybe older firmware?

the prius does however excel in town for mpg though.

The SAHM article doesnt mention "lean burn" or use any sort of word or term to suggest that, so I assumed SAHM didnt mean lean burn.

So in order to get SAHM evoked I need a scangauge? Is there some specific one for the HCHII? Please help me hon

I really attached to this car now actually emotionally attached at that.

 

The dealer can reprogram the firmware with patches from Honda.

Again, owning 3 Prius and 4 Honda IMA, I think your perceived difference between the two is misplaced. The Prius excels primarily because of a more complex and robust system with a far superior battery pack even though they are made by the same company, with the same capacity and same internal resistance.

HOWEVER, one can readily narrow that gap to be nearly indistinguishable between the two.

WHEN I had a healthy battery in the HCH2, I could readily get 51-52mpg with the Ecopias on it. This was primarily 45mph surface streets. About 1.5 miles of highway out of 14 miles total distance. I could do it for a full tank. Note that I couldn't get anywhere near this with A/C use.

If you're getting 38+ in city driving with A/C use, you're at the Prius level. Prius A/C is completely electric, and it consumes 2000W of electrical power most of the time when its on. When it reaches its set point and the cabin is actually comfortable, it drops to 800W or so.

All the techniques and limitations described for SAHM are identical to lean burn. You do not need a scangauge, but you can use it to confirm you're in it. Just get the standard one. Torque Pro with a bluetooth OBD2 ELM327 reader can do it as well.

If you're not getting 38+mpg with very conservative city driving and moderate A/C use, your battery is likely marginal.

Have you ever noticed the battery at two bars?

 

After about some time driving, the in city mpg is actually around 38mpg for me, which is also the prius level? I always assumed prius did 50 plus in city with a/c on and non conservative driving. I dont have LRR tires, but I did increase psi to compensate at 40 psi vs the 32 psi oem. I have yet to go to 50 or 60.

The battery level bars are something of a mystery to me, at times its not charging and them suddenly goes up to 8 or 10, whatever the max is. I dont quite understand how it operates.

 

This morning, 08 Prius with 172mi on the trip meter. Mpg meter says 40.1. Full ac use and not conservative.

Prius mpg meter also optimistic by about 5%. Both my hch2 were conservative by 2-5%.

No matter how much you inflate standard tires you will still be 2mpg short on 40psi LRR.

The gauge behavior you describe confirms you have a marginal battery. It is repeatedly re calibrating itself to compensate for imbalance.

AGAIN, have you ever seen 2 bars on the SOC gauge?