Frustrated that my auto stop has all but stopped working on my 6 mile drive to work now that the morning temp's have dropped into the high 30's & low 40's.... I have tried an experiment the last 2 days, both days were in the high 30's (38 & 39).
I ordinarily drive with the heat on auto, 70 & a/c off, defroster off, I start getting warm air within a few minutes but no auto stop.
The last 2 days, with the heat off completely by pushing the "off" button, I got auto stop within 2 miles.
Tonight on the way home, it was 42, I left the heat off & had auto stop within 2 miles. Turned on the heat, & at the next and every subsequent signal, had no auto stop.
This is not a controlled scientific experiment by any means only a interesting observation.....will I go without heat this winter, I would find that no worse than going without A/C in the summer, so the answer is NO, I will have heat, I will have A/C It is just nice to know that my choices may cost me a few cents.

The HVAC controller is tightly integrated into the entire IMA system. An issue with it will effect Autostop.

The challenge is that most Techs will not check the HVAC system for what are perceived as an engine/transmission issue.

You might want to visit a dealer explain the issue with autostop, and ask them to check if there are any codes stored in the HVAC module.

I had a similar situation with autostop and it took the dealer a week to figure it out. It is fixed now, and now my MPG is up 25%.

Oops, apparently I didn't state my case properly.

Auto stop works fine, after about 10 miles with the heat on it stops every time, it just takes longer to warm the car up on cool day (10 miles) than I drive to & from work (6 miles).

I was frustrated because when it is 90 outside, I get Auto stop within a few blocks, now that it is cooler, it is taking me several miles to get it to work.....the heater is drawing heat off the engine therefore making the car take longer to warm up completely.

I am not saying the auto stop does not work, just not as quickly as when it is warm out.

does that make better sense?

It is interesting that Honda did not use an eletrical based heater element like Ford does on the new F-150 Super Duty Pickup Truck.

Honda does use an electrical A/C element in this car......

Anywho.. I will saciface my mileage for comfort.. Freezing is not worth an extra 20 cents savings....

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1987 Chevy Spectrum - 200,000+ Miles -Junk Yard
1994 Honda Civic DX Coupe - Truck Hit it
1998 Acura 2.3 CL - End of Lease
2002 Acura TL 3.2 - End of Lease
2004 Acura MDX - End of Lease
2007 Mercedes ML350 -Lemon
2007 Honda Civic Hybrid w/Navi - Active

And I thought I was suffering MPG loss. It's about 50 F here and it takes about a mi to warm up to autostop. Good thing to, cuz about a mile later, I get off the freeway and wait through 6 consecutive (80% red) lights.

You could try blocking the air flow thru. your grill, and you will find your auto- stop will activate sooner. I use those foam pipe insulators over the gril bars. Temp never goes past mid way. Car gets up to temp in half the time. H

I too notice longer drives before regen and auto stop kicks in (assist is still available), no doubt due to colder outdoor temperatures. What I have noticed is that the water temperature can be up to its normal operating temperature, but the auto stop takes a little longer still before it will activate. Whereas, during warmer weather the water temperature can be low and yet the auto stop activates nonetheless.

So, what I gather from this is that there are other temperature-sensitive components in the car that affect auto stop but are not necessarily related to the engine's water temperature, nor even localized radiant heat from the engine. Is it just the battery pack?

Harold:
What range of temps are you doing this in? I was thinking about it, but I'm not really sure if it will have an effect in my 50F weather. And I would also like to be able to drive (for a couple of hours at most) when it gets up to 70 or 75 w/o removing this.
Anyone have thoughts?

I am getting a little frustrated in the mornings of the past month that have been 40-50 deg and AS taking so long to engage. It's even more frustrating when I go about 3 miles and come to a stoplight, the car does go into AS, then after about 20 seconds sitting at the light in AS it decides "oops, I don't want to be in AS yet" so the engine starts back up (I know someone is going to say I probably adjusted my foot on the brake so it started back up, and I would agree if this only happened once, but it's happened at least 20 times!).

So I have been thinking (like Spinner above) about the other factors for AS to engage. I have been checking the engine temp gauge in the morning, afternoon, and evening when the first AS engages. It looks to me like it has nothing to do with engine temp because I've seen AS engage at 1 or 2 blips on the gauge as well as 6 or 7 blips. In the morning about 7am when it's about 40-45 deg, it's taking about 4-5 miles for AS to engage and looking at the temp gauge I've seen up to 5 or 6 blips before AS engaged. My regular job is only about 7 miles from the house, and about 2 miles before work I drop off my daughter at school. So the car sites for 3-3 1/2 hours, and with a cold engine around 10:30am (it may be around 55-60 by this time) I can drive 3/4 mile down the road to the post office and get AS to engage with 1 or 2 blips on the temp gauge. Then after coming out of the post office and starting the engine to go back to work, AS will engage after about 500-700 feet.

So to me if engine temp plays a role in AS, it's not a very big one. I'm sure a block heater would help with mpg and getting the engine warmed up quicker, but I still don't think it would make a difference with the factors for AS to engage (someone with a block heater please chime in and agree or disagree).

Which then got me to thinking isn't one of the factors battery temp? If the battery is too cold (or overheats) AS does not engage. Isn't that the part of the trick behind the HCH battery hack switch to make the onboard computer think the battery's temp is out of range so assist will not occur and drain the SoC? So I was thinking has anyone tried a battery heater? Maybe something in the trunk up against the battery compartment to warm that up before they start in the morning? I don't know... this is just a thought, but it seems pretty plausable. Mythbusters where are you Help us test the right conditions for an HCH to AS!

Colbey, I have had my gril blocked for a mth. now. Below 55 degree. I believe the car could still handle warmer temps.. The temp. of the ice never climbs above half way, but does get up there faster. You can switch between temp and instant mpg and watch it untill you get comfortable with it. I believe some air does get by the foam, but it makes a big differance. Try it H