Hi folks,
I have had this issue since I bought the car in 2006 (HCHII).
During random times- almost as if nearing the threshold where auto stop decides to kick in- when I stop- the rpms will up to 750 and then down to near zero- then back up again- as if it is trying hard to go into auto stop but never can get there. Now, it is happening daily. I usually drop it into Nuetral and it goes away- but as soon as I pop it into drive- it will start up again. When I lift my foot of the brake- it will keep doing it (which doesn't make sense as autostop should disengage at that point).

This morning, trying to get over a snow rut in the road- I almost stalled it for the first time- even though I started to give it gas- it stilled try to go into auto stop.

Anyone ever have this experience. I am glad I bought the full 7 year extended warranty (I assume this is something that would be covered). Getting a little worried about these things now.

 

It will typically do this when the car is not quite warm enough to engage auto stop. It will engage when it's warmed up to around 160+F. If you had SGII, you could tell what the temp is at the time it's doing it.

It doesn't sound too unusual, although I can't imagine why it tried to stall on you.

Jess

 

The brake pedal switch might be out of adjustment and it doesn't see your foot on the brake pedal all the time when cold. It can act like you lifted you foot off the pedal - only you are not pressing as hard as you did to stop.

 

Just for ***** and giggles, make sure there is no winter floor mat creeping up and starting to nudge the gas peddle.

I find with my winter mat protocol in place, I must re-adjust the top mat after awhile as it gently creeps up. The only way I notice: the car wants to idle stop and really tries to, but just gets an idle that wavers up and down instead of text book steady....

I use the heel of my right shoe to "grab and pull" the mat away from the bottom of the gas peddle and problem solved.

 

Nope, not a mat issue (as I don't have the reving issue when in neutral). I really think it is a faulty temperature gauge or something- anyone know what parts control when auto stop kicks in. I feel that I am just at that threshold where it wants to go into AS but has a conflict (it's like the engine is not allowing it to happen and thus the software kicks into keep the engine on). Something to that effect.

 

I would also check that the A/C and both defrosters are off. I've read posts like this and it was because the rear defroster was on.

If everything is off, and it behaves like this in both cold and warm weather, I would take it in. This is one of the primary things this car does to save fuel and if it's not working, it needs to be addressed.

Jess

 

Why don't you just ask the dealer? They can only say either take it in for us to check or they will tell you what the problem is, if they know.
Our Honda dealer here is pretty good at showing you how things are fitted and so on so that you can do simple things yourself but, I would imagine any work costing real money and concerning the smooth running of engine parts they would want to do themselves.
At a guess I would say the engine speed sensor may be faulty, sometimes happens coz electronics don't like to be hot and sensors typically are near hot parts. I don't know much about it but, I would imagine if you could find out it might turn out to be a simple swap out. It could be the automatic choke sticking (if there is such a thing nowadays). I assume this does not happen when you drive around in 'S' mode. The revs can drop just as low but, obviously the car won't go into autostop. Ask the dealer first.

 

I think you are missing the point that a lot of dealers will not do much if they do not see the issue happening with their own eyes. And in listening to the Toyota hearing- I am even more convinced that everyone should watch out. Luckily, I was able to capture this issue on my iphone for proof that it happens.

 

If it does this all the time when you are stopped, it sounds like a good old fashioned vacuum leak somewhere. I used to track down vacuum leaks by spraying carburetor cleaner on different vaccuum hoses until the engine idle changed repeatedly when sprayed on one spot. That would usually pinpoint the problem pretty quickly.

Good luck.

 

When our 07 HCHII had an auto-stop problem like the one you describe, no one could find anything wrong with the systems generally associated with auto-stop. Finally they did a fault dump of all of the system controllers, and found a fault with the HVAC controller. They replaced that controller, and the auto-stop feature has worked flawlessly ever since. As a side note, Honda kept the car for 4 days trying to solve it. They had guys not only from my dealer, but also Honda USA, and Japan.

If your dealer has not looked at all systems for faults, then they might not have looked deep enough yet.