is this normal?

[dzucc]

I've had my 07 Prius for about a month. Within the last week ( and the onset of cold weather 20F. ) when I start out with the car not warmed up, when I accelerate moderately strong it sounds like a coventional car with a slipping clutch. Is this normal?

[Vincent]

<div class='quotetop'>QUOTE(G-IVSP Pilot @ Jan 24 2007, 03:28 AM) [snapback]379949[/snapback]</div>

I've had my 07 Prius for about a month. Within the last week ( and the onset of cold weather 20F. ) when I start out with the car not warmed up, when I accelerate moderately strong it sounds like a coventional car with a slipping clutch. Is this normal? [/b]

What's the State of Charge (SOC) of your main battery? If it's low, you're accelerating with the cold engine only and that will make a loud slipping sound.

[efusco]

What do you mean...what sound do you hear? If high RPM it may just be related to the cold battery not being able to deliver as much energy as you're used to on warm mornings.

In any case, the ICE has a rev limiter and although it may sound fast/loud/scary it's not doing any harm. Just keep on driving.

[qbee42]

As Evan suggests, it's probably just the engine taching up. It's a bit disconcerting on the Prius, since the engine speed has no direct correlation with car speed; that's where the "slipping clutch" sound comes from. The control unit on the Prius runs the engine at that best speed for the power it needs.

Tom

[JayGoldstein]

<div class='quotetop'>QUOTE(qbee42 @ Jan 24 2007, 08:36 AM) [snapback]380008[/snapback]</div>

As Evan suggests, it's probably just the engine taching up. It's a bit disconcerting on the Prius, since the engine speed has no direct correlation with car speed; that's where the "slipping clutch" sound comes from. The control unit on the Prius runs the engine at that best speed for the power it needs. Tom[/b]

What Tom and Evan said.

This is my first winter with the Prius, so I'm still discovering how it behaves in cold temperatures. Last week, I took it on the highway when the temperature was -29C (-20F) [the wind chill was something like -38C (-36F)]. I could tell that the engine was running at much higher rpm than normal - it felt like driving a car with a manual transmission on the highway in 4th gear rather than 5th. This was confirmed by the MFD. At 105 km/h (65 mph) it showed around 8.2 l/100 km. In less extreme cold, I usually get around 6 l/100 km at the same (or even higher) speed.

[Ken Cooper]

<div class='quotetop'>QUOTE(G-IVSP Pilot @ Jan 24 2007, 01:28 AM) [snapback]379949[/snapback]</div>

I've had my 07 Prius for about a month. Within the last week ( and the onset of cold weather 20F. ) when I start out with the car not warmed up, when I accelerate moderately strong it sounds like a coventional car with a slipping clutch. Is this normal?
[/b]

Yes. I experience this on cold mornings where I live, especially when going up a slight incline. And the slipping clutch sound is due to the continuous variable transmission and the manner in which it works with the engine (and generators/motor) Although the Prius CVT is very different from CVTs in other cars, all cars with CVT, including ours, will, under certain conditions, give you that slipping clutch sound.

[JimN]

<div class='quotetop'>QUOTE(G-IVSP Pilot @ Jan 24 2007, 03:28 AM) [snapback]379949[/snapback]</div>

I've had my 07 Prius for about a month. Within the last week ( and the onset of cold weather 20F. ) when I start out with the car not warmed up, when I accelerate moderately strong it sounds like a coventional car with a slipping clutch. Is this normal?
[/b]

Blocking your grill will help solve your winter problems. Look for the thread and choose the materials and installation style you like best. Probably the best return on investment of any mod. Also pump your tires to 42/40.

[dzucc]

<div class='quotetop'>QUOTE(Vincent @ Jan 24 2007, 04:39 AM) [snapback]379956[/snapback]</div>

What's the State of Charge (SOC) of your main battery? If it's low, you're accelerating with the cold engine only and that will make a loud slipping sound.
[/b]

SOC is 3-4 bars. But this mostly happens when the car has sat for an hour or so. It's finally cold here in Chicago!

<div class='quotetop'>QUOTE(Vincent @ Jan 24 2007, 04:39 AM) [snapback]379956[/snapback]</div>

What's the State of Charge (SOC) of your main battery? If it's low, you're accelerating with the cold engine only and that will make a loud slipping sound.
[/b]

SOC is 3-4 bars. But this mostly happens when the car has sat for an hour or so. It's finally cold here in Chicago!

<div class='quotetop'>QUOTE(G-IVSP Pilot @ Jan 24 2007, 10:54 PM) [snapback]380468[/snapback]</div>

SOC is 3-4 bars. But this mostly happens when the car has sat for an hour or so. It's finally cold here in Chicago!
SOC is 3-4 bars. But this mostly happens when the car has sat for an hour or so. It's finally cold here in Chicago!
[/b]

To everyone who has answered my thread...Thanks!! I don't feel so alone in the Prius world anymore.
David

<div class='quotetop'>QUOTE(efusco @ Jan 24 2007, 06:43 AM) [snapback]379974[/snapback]</div>

What do you mean...what sound do you hear? If high RPM it may just be related to the cold battery not being able to deliver as much energy as you're used to on warm mornings.

In any case, the ICE has a rev limiter and although it may sound fast/loud/scary it's not doing any harm. Just keep on driving.
[/b]

Thanks Evan. I'll just keep on driving.

[dzucc]

<div class='quotetop'>QUOTE(JimN @ Jan 24 2007, 08:58 PM) [snapback]380426[/snapback]</div>

Blocking your grill will help solve your winter problems. Look for the thread and choose the materials and installation style you like best. Probably the best return on investment of any mod. Also pump your tires to 42/40.
[/b]

Jim,
I checked out that thread and I will be going to home depot tomorrow.
David