Shift Problem while Accelerating

nworden9 · 10-06-2007, 09:45 PM

Can anyone help me with this?

I have a 2006 Prius with 24000 miles. Once every week, or so, the transmission acts unusual when accelerating onto the expressway -- it doesn't want to 'upshift' while accelerating. Here's what happens...

1) The car has been driven for at least 30 minutes at highway speed.
2) Then the car sits for 5 to 15 minutes (rest area).
3) Then the car accelerates back onto the expressway; however, the transmission does not want to 'shift' into the final CTV ratio.

Thanks!

Manksgloob · 10-06-2007, 09:50 PM

I'm not sure I have an answer as to why it would do that, but you mention that this is a problem.
Do you mean that due to the transmission not "shifting" to the final ratio that you are not getting the full acceleration onto the expressway that you were expecting?
Also, how far down are you stepping on your accelerator?

<div class='quotetop'>QUOTE(alt_fuel @ Oct 6 2007, 06:45 PM) [snapback]522301[/snapback]</div>

Quote:

Can anyone help me with this?

I have a 2006 Prius with 24000 miles. Once every week, or so, the transmission acts unusual when accelerating onto the expressway -- it doesn't want to 'upshift' while accelerating. Here's what happens...
1) The car has been driven for at least 30 minutes at highway speed.
2) Then the car sits for 5 to 15 minutes (rest area).
3) Then the car accelerates back onto the expressway; however, the transmission does not want to 'shift' into the final CTV ratio.

Thanks!
[/b]

**efusco** · 10-06-2007, 10:06 PM

The gears are fixed, there is never any shifting and there are no ratios to shift into.
I think you need to describe the symptoms rather than what you think the problem is and we're more likely to be able to help you.

qbee42 · 10-06-2007, 10:30 PM

Ditto what Evan says. The Prius transmission never shifts, clutches, or otherwise change gears. It feels like a CVT, but it's not really that either.

Tom

patsparks · 10-07-2007, 05:19 AM

to make the engine go slower lift your foot.

donee · 10-07-2007, 10:01 AM

Hi Alt_fuel,

What Evan and Gbee said is all true. So, I am going to guess as to what you are experiencing. It sounds like you belive the car has slow accelleration after sitting at the rest stop. This could be due to low SOC (Battery State Of Charge). When the battery is low, the car will use the engine for charging, rather than quick accelleration. Sitting at the rest stop in the sun with the car on, with the AC on for 15 minutes will bring the SOC down. As the engine wont run with the car in park until the battery is at a pretty low level (purple bars). So, driving down the exit ramp from the rest stop, the first time the engine has run in a few 10's of minutes, the engine is given a charging priority by the computer. To get the battery to last the life of the car, when the battery is low, the engine must recharge it as a priority whenever the engine is required to run.

drifty1955 · 10-07-2007, 10:02 AM

<div class='quotetop'>QUOTE(alt_fuel @ Oct 6 2007, 09:45 PM) [snapback]522301[/snapback]</div>

Quote:

Can anyone help me with this?

I have a 2006 Prius with 24000 miles. Once every week, or so, the transmission acts unusual when accelerating onto the expressway -- it doesn't want to 'upshift' while accelerating. Here's what happens...
1) The car has been driven for at least 30 minutes at highway speed.
2) Then the car sits for 5 to 15 minutes (rest area).
3) Then the car accelerates back onto the expressway; however, the transmission does not want to 'shift' into the final CTV ratio.

Thanks!
[/b]

Yes the CVT does not shift like a standard AT. In fact no shifting at all. Its my first CVT and I keep expecting it to upshift and it doesn't. Very used to it now and its nice. Also very pleasantly surprised at how quick the car is if properly gas pedaled.
Any trans issues I would take a real good peak under the CVT and look for leaks especially around the little filter pan under the CVT. In my travels I have found a little oil change joint that allows me to look under the car with every change. Not to many of those left. I usually duke the kid changing the oil filter down there $5 and then its no problem sir come on down. You'd be surprised the things you can check and or head off if you know what to look for. That kid can check the bolt hole fill hole of the CVT and check with your finger if the fluid is up to the hole and if it looks and smells good. At 24K I would expect it to look very good and smell fairly new but I don't know how hard you have been on your baby. If it was me any silliness out of the trans and the fluid is first to go. I would get the CVT fluid replaced. Its very cheap insurance. If the dealer wants to talk you out of it you could go to any garage with 5 quarts of Toyota WS fluid. But since its not in there standard ATF fill drum with there squirt tool you might have to provide a little hand pump found at any auto store. Its pretty easy and have done it many times in my driveway to other cars. Please let us know what you find and good luck.

efrench515 · 10-07-2007, 10:19 AM

<div class='quotetop'>QUOTE(alt_fuel @ Oct 6 2007, 09:45 PM) [snapback]522301[/snapback]</div>

Quote:

Can anyone help me with this?

I have a 2006 Prius with 24000 miles. Once every week, or so, the transmission acts unusual when accelerating onto the expressway -- it doesn't want to 'upshift' while accelerating. Here's what happens...
1) The car has been driven for at least 30 minutes at highway speed.
2) Then the car sits for 5 to 15 minutes (rest area).
3) Then the car accelerates back onto the expressway; however, the transmission does not want to 'shift' into the final CTV ratio.

Thanks!
[/b]

I suspect that you are just in low power mode, while setting at the rest area for the 5-15 minutes, with possibly the A/C on your SOC is probably in the purple. This will cause you to accelerate slowly and you may even notice that the engine sounds like it is running at a higher RPM for a little bit. This is normal operation.

donee · 10-07-2007, 10:22 AM

Hi Alt_fuel,

Another possibility is that you are running down the highway with the AC off, and then park the car windows up. While driving the car there is plenty of air-flow into the battery, and it stay cool. But just like a hot engine, it needs continued airflow coming to a stop after running on the highway to avoid spiking in temperature. If the battery is hot, the hybrid system will not let it deliver much power to the transmission.

I find that when temps are over 82 F, I roll up the windows, and run with the AC at 80 F to keep the battery cool. Otherwise the car gets a little hinky in the stop and go traffic after my highway run. The extra energy used by the AC is made up for by being able to pulse and glide like normal after gettting off the highway.

richard schumacher · 10-07-2007, 05:31 PM

<div class='quotetop'>QUOTE(alt_fuel @ Oct 6 2007, 08:45 PM) [snapback]522301[/snapback]</div>

Quote:

1) The car has been driven for at least 30 minutes at highway speed.
2) Then the car sits for 5 to 15 minutes (rest area).
[/b]

Sits how, exactly? Do you leave it ON and in Park? Do you turn it to ACC or IG-ON and run the A/C or some accessories?

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10-06-2007, 09:45 PM	#1
nworden9 Join Date: Jun 2006 Posts: 6 My Car: Package: Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	Can anyone help me with this? I have a 2006 Prius with 24000 miles. Once every week, or so, the transmission acts unusual when accelerating onto the expressway -- it doesn't want to 'upshift' while accelerating. Here's what happens... 1) The car has been driven for at least 30 minutes at highway speed. 2) Then the car sits for 5 to 15 minutes (rest area). 3) Then the car accelerates back onto the expressway; however, the transmission does not want to 'shift' into the final CTV ratio. Thanks!

10-06-2007, 10:06 PM	#3
efusco Troll Slayer Join Date: Nov 2003 Location: Nixa, MO Posts: 14,225 My Car: 2004 Prius Package: #9 Nominated 1 Time in 1 Post TOTM Awards: 0 Friends: 24	The gears are fixed, there is never any shifting and there are no ratios to shift into. I think you need to describe the symptoms rather than what you think the problem is and we're more likely to be able to help you.

10-06-2007, 10:30 PM	#4
qbee42 Senior Member Join Date: Mar 2006 Location: Northern Michigan Posts: 5,643 My Car: 2006 Prius Package: #7 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 6	Ditto what Evan says. The Prius transmission never shifts, clutches, or otherwise change gears. It feels like a CVT, but it's not really that either. Tom

10-07-2007, 05:19 AM	#5
patsparks Uneducated bird-brain Aussie Join Date: Jul 2007 Location: Adelaide South Australia Posts: 4,905 My Car: 2004 Prius Package: Base Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 17	to make the engine go slower lift your foot.

10-07-2007, 10:01 AM	#6
donee Senior Member Join Date: Aug 2005 Location: Chicagoland Posts: 1,536 My Car: 2006 Prius Package: #2 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	Hi Alt_fuel, What Evan and Gbee said is all true. So, I am going to guess as to what you are experiencing. It sounds like you belive the car has slow accelleration after sitting at the rest stop. This could be due to low SOC (Battery State Of Charge). When the battery is low, the car will use the engine for charging, rather than quick accelleration. Sitting at the rest stop in the sun with the car on, with the AC on for 15 minutes will bring the SOC down. As the engine wont run with the car in park until the battery is at a pretty low level (purple bars). So, driving down the exit ramp from the rest stop, the first time the engine has run in a few 10's of minutes, the engine is given a charging priority by the computer. To get the battery to last the life of the car, when the battery is low, the engine must recharge it as a priority whenever the engine is required to run.

10-07-2007, 10:22 AM	#9
donee Senior Member Join Date: Aug 2005 Location: Chicagoland Posts: 1,536 My Car: 2006 Prius Package: #2 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	Hi Alt_fuel, Another possibility is that you are running down the highway with the AC off, and then park the car windows up. While driving the car there is plenty of air-flow into the battery, and it stay cool. But just like a hot engine, it needs continued airflow coming to a stop after running on the highway to avoid spiking in temperature. If the battery is hot, the hybrid system will not let it deliver much power to the transmission. I find that when temps are over 82 F, I roll up the windows, and run with the AC at 80 F to keep the battery cool. Otherwise the car gets a little hinky in the stop and go traffic after my highway run. The extra energy used by the AC is made up for by being able to pulse and glide like normal after gettting off the highway.