Spontaneously aborted S4 glides at 26 MPH

JimboK · 08-09-2007, 07:44 PM

Thanks for the responses. What everyone says makes sense, and the agreement seems to be that the heat, especially in the battery, was the cause.

But again, has anyone seen a glide interrupt itself part-way through? Why at a consistent 26 MPH? And why did the anomaly stop even though the battery temp didn't change after that? I welcome educated guesses in the absence of first-hand experience or knowledge.

hobbit · 08-09-2007, 09:03 PM

The threshold of how much current you can draw probably went down,
so the whole system probably became much more sensitive to demand.
The other little wrinkle is that short period of engine-running when
the secondary cooling loop opens via the 3-way valve; the engine
tends to run long enough for the water pump to push stuff through
that piece of the loop [incl. the bottle] and make sure it's all
warm. That can yield a small period of frustration, but then it
sorts itself out again. Yup, it happens in stage 4 too.
.
_H*

rsforkner · 06-12-2008, 10:27 AM

I don't think this is too far off topic....
Where does the exhaust air from cooling the battery go? Is it vented outside the car or back into the passenger compartment?

If outside, where is the vent and how does blowing all that cool air outside affect the AC load? I know it is needed to cool the battery but just wondered about the additional load on the AC. Just sounds like driving a "regular" car AC with the windows down.

Bob

**efusco** · 06-12-2008, 10:49 AM

The air exits near the 12v battery on the back rear side of the car to the outside of the vehicle. I have a really nice photo, created by Wayne Brown, that I like to post that shows the air flow very nicely, but my dang work blocks my image hosting site....bastards.

Fred_H · 06-12-2008, 12:36 PM

Quote:

Originally Posted by JimboK

... Why at a consistent 26 MPH? ... I welcome educated guesses in the absence of first-hand experience or knowledge.

The only thing that comes to my mind is that 26 mph is around the speed where MG1 changes direction when the ICE is idling.

Danny Hamilton · 06-12-2008, 12:53 PM

Quote:

Originally Posted by efusco

. . . .but my dang work blocks my image hosting site. . . .

So, you'll post it tonight, right?

06-12-2008, 10:27 AM	#13
rsforkner Senior Member Join Date: Apr 2008 Location: Boynton Beach, FL, USA Posts: 344 My Car: 2008 Prius Package: #2 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 1	Re: Spontaneously aborted S4 glides at 26 MPH I don't think this is too far off topic.... Where does the exhaust air from cooling the battery go? Is it vented outside the car or back into the passenger compartment? If outside, where is the vent and how does blowing all that cool air outside affect the AC load? I know it is needed to cool the battery but just wondered about the additional load on the AC. Just sounds like driving a "regular" car AC with the windows down. Bob Last edited by rsforkner; 06-12-2008 at 10:27 AM. Reason: typo

06-12-2008, 10:49 AM	#14
efusco Troll Slayer Join Date: Nov 2003 Location: Nixa, MO Posts: 14,201 My Car: 2004 Prius Package: #9 Nominated 1 Time in 1 Post TOTM Awards: 0 Friends: 24	Re: Spontaneously aborted S4 glides at 26 MPH The air exits near the 12v battery on the back rear side of the car to the outside of the vehicle. I have a really nice photo, created by Wayne Brown, that I like to post that shows the air flow very nicely, but my dang work blocks my image hosting site....bastards.

08-09-2007, 07:44 PM	#11
JimboK One owner, low mileage Join Date: May 2006 Location: Chesterfield, VA Posts: 1,990 My Car: 2005 Prius Package: #2 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 3	Thanks for the responses. What everyone says makes sense, and the agreement seems to be that the heat, especially in the battery, was the cause. But again, has anyone seen a glide interrupt itself part-way through? Why at a consistent 26 MPH? And why did the anomaly stop even though the battery temp didn't change after that? I welcome educated guesses in the absence of first-hand experience or knowledge.

08-09-2007, 09:03 PM	#12
hobbit Senior Member Join Date: Mar 2005 Location: Bahstahn Posts: 2,975 My Car: Package: Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	The threshold of how much current you can draw probably went down, so the whole system probably became much more sensitive to demand. The other little wrinkle is that short period of engine-running when the secondary cooling loop opens via the 3-way valve; the engine tends to run long enough for the water pump to push stuff through that piece of the loop [incl. the bottle] and make sure it's all warm. That can yield a small period of frustration, but then it sorts itself out again. Yup, it happens in stage 4 too. . _H*