RPM slow to return to idle

No, but my tests on my vehicle shows that the battery runs hotter and takes longer to cool on recirc. The actual volume of air the battery fan can push over the battery is reduced.

 

The spare tyre well is inside the car. However, located behind the 12 volt battery on the left and the right hand under floor luggage compartment, there are two vents to the outside though which the battery cooling air is vented from the tyre well. If you restrict the inflow of air it logically follows that you reduce the outflow of air. I'm not arguing whether recirc is good or bad simply the physical fact that it reduces air flow and there by impairs cooling.

 

sounds like if i leave it in recirq, i might asphyxiate myself.

 

That's why they don't allow recirc to totally shut off outside air.

When I drive through the tollway tunnels here, I put ventilation into cabin filter mode. That's usually long enough to get through the tunnel. Sometimes I have to press it again if travel is slow.

 

My car does the same thing, usually on 100+ degree days at high speeds or going up hills.

 

Our is 2010 also. Around 100k. Started doing the same thing last year.

Floor the pedal, or quickly accelerate and the engine remains at high rpm long after removing foot from the accelerator.

Was your dealer able to find a solution or did they simply document the issue? It's somewhat unnerving when you consider the potential for an accident if the engine were to engage. Although it was limited to a only few cases, unintended acceleration has happened in the past. I keep my fingers crossed that this isn't part of the problem or an early warning.

A mechanic buddy of mine suggested it was mechanical and not electronic in nature, but you said throttle cleaning had no effect? He also recommended that a run a bottle of Lucas fuel treatment through a tank of gas. Have you tried anything like that?

 

No resolution. The dealership service shop logged 120 miles collecting data and replicating the problem back in August(?). Didn't cost me anything. Once they experienced the problem, they were just as curious as I was. So, their top mechanic and prius expert spent three solid days collecting all the data they could and cleaning/inspecting anything they thought would be the cause. All of this was reported to Toyota through official channels. The word back from Toyota was that it is normal, but I received no further explanation regarding the actual source of the experience.

Since it is all well documented and occurred before the end of my extended warranty, I'm covered should it worsen and result in a more catastrophic failure.

If I learn anything new, I'll be sure to post here for those seeking answers to the same problem!

 

This is “exactly” what mine did yesterday and thought, damn what now. AC running recirc., hot outside maybe 85, punched the gas pedal to get into traffic and noticed engine slow to idle. Then while in drive noticed when coming to a stop sign the engine would not quit like normal. I didn’t notice battery level but probably was over half or better. Parked it. Today it is like nothing happened. This has happened in the past. Why does it do this?

 

Eight-year-old post, I know, but worth mentioning that it's explained in the New Car Features manual that the ECU managing the battery cooling holds a veto over recirc mode. It will tell the A/C to switch to fresh if it wants more air.

I don't know if that changes the control panel LED showing which mode you've selected, or just happens in secret.

 

I am actually going to consider this as normal, as there is no ck eng light. I’m getting 50-60 mpg. 132K miles 2015

Ok. It happened again today but momentarily. Really have only noticed it the last year and has only did it maybe 4 times. Thank you for the kind response! Drmax

 

Ok. Just reread what you wrote. Can’t imagine this causing the engine to take so long to return to idle. (an air conditioning deal) I will keep an eye on it. About 90 here today Indiana. But it is doing exactly what that other fella wrote that I quoted. Seems odd. Thx

 

My 2010 is doing the same thing now!
Anyone figure out how to fix it?
In florida, ac on and hot days….

 

I'm guessing it's normal. It's just the HVB and engine both wearing out and possibly the combination of hot weather. If you just punched it, the engine could be holding high idle in case it gets punched again, to leave the HVB alone, either because it's hot or low charge or high demand from AC.

I've got a 2010 with 196k and have noticed it about 2 years ago and now that I'm looking to replace the HVB, it's bad in the heat. The A/C in my car has always sucked. I'm not sure if it's related to my HVB or condenser or something else.