Shift Problem while Accelerating

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>

 

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

 

to make the engine go slower lift your foot.

 

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.

 

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

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.

 

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

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.

 

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.

 

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

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?

 

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

was your battery low? (you mentioned it sitting) if the battery is low, you lose a portion of electrical assist, or low speed electric. the car will fill the battery back up over a period of a couple blocks. even a little regen breaking will possibly put you into green state (battery)


the way the car sounds... it's never exactly the same. it all depends on the ratio of gas to electric. if you're going up a really long pass and speeding up the entire way.. .. there is a good chance your engine will run at high rpms.. making it sounds like a frantic vacuum... when you go back down the hill and your regenerative braking system.. and regen while coasting.. will fill your battery up.

if the car ever has a serious problem.. that big dummy triangle on the dash tends to light up.. along with all his other warning buddies.

sorry if this sounds repetative. my browser isn't showing everything.

 

In that case simply turning the car OFF while you're at the rest stop should fix things. Leaving it ON with the A/C running, the car keeps the battery charged but only at a minimal state, which means that less energy is available for launch. Higher RPMs is completely normal for that situation.

 

<div class='quotetop'>QUOTE(alt_fuel @ Oct 7 2007, 10:22 PM) [snapback]522576[/snapback]</div>

The Prius engine can really sound fast if you put your foot into it. It's not that fast, as the RPMs are limited by the computer, but it's a bit disconcerting until you become accustomed to it. If you need the acceleration, don't hold back just because the engine races. You can't hurt it.

Tom

 

The engine in the Prius wont rev all that high, I think it will only rev to about 4500rpm but the engine in a Yari which is roughly similar would red line around 6500rpm.

You won't hurt your prius with high revs.