Having trouble accelerating??

LisaM · 09-10-2007, 05:09 PM

Yeah I'm definitely in D....but it kinda seems like that- like if it were a manual, and I was in the wrong gear...

Who knows...I'm going to have my husband drive it later and see what he thinks...then maybe drop it at the dealer AGAIN!!!

Thanks

**efusco** · 09-10-2007, 06:01 PM

make sure the parking brake isn't on.

richard schumacher · 09-10-2007, 06:03 PM

Don't be offended: is there any chance that the parking brake is engaged? This would not be the first time...

donee · 09-10-2007, 08:06 PM

Hi LisaM,

The parking brake is unusual. To be sure you have completely released it, you need to press down, the pull up with your left foot smoothly until your foot no longer is touching the pedal. If you stop anywhere along the release of the pedal, before the pedal is no longer touching your foot, you will have set some braking force.

Additionally, some PC members have found that if the parking brake was not released, and the driver used the full torque of the motor during reversing, it can mal-adjust the brake so that it will not release 100 %. That is, reversing with the brake partially engaged causes the brake to adjust up too tight. If the car does not easily roll backwards with just a little bit of pedal, stop, and recheck that you have fully released the brake. To do this, one resets the brake, then re-releases it.

Have the dealarship put the car on the lift, and reset the rear brakes. With the car on the lift, and the brake off, the wheels should be easy to spin. If not, have the rear brake adjusters reset. Then proper operation of the brake pedal will bring the brake setting into a correct amount of play.

You should not have trouble doing 70 mph. Hell, it should be hard to not do 70 mph in a Prius, due to its smoothness, and quiet nature.

You also need to use the parking brake. Using it resets the rear brake adjustment automatically. If its not properly adjusted, the amount of hydraulic slop in the system will be large, and this could make the switchover from electric to hydraulic braking jerky. Which might cause an unexpected reduction in braking power as one pulls in behind a stationary vehicle.

Sarge · 09-11-2007, 10:14 AM

Hmmm... I check back in here, and I agree with others that this no longer sounds normal.

The parking brake does sound like a likely culprit. If you put the car in Drive or Reverse but then not touch the accelerator, does the car crawl as normal? This could be an easy indicator of a non-releasing parking brake...

qbee42 · 09-11-2007, 11:01 AM

<div class='quotetop'>QUOTE(donee @ Sep 10 2007, 08:06 PM) [snapback]510334[/snapback]</div>

Quote:

Hi LisaM,

The parking brake is unusual. To be sure you have completely released it, you need to press down, the pull up with your left foot smoothly until your foot no longer is touching the pedal. If you stop anywhere along the release of the pedal, before the pedal is no longer touching your foot, you will have set some braking force.

Additionally, some PC members have found that if the parking brake was not released, and the driver used the full torque of the motor during reversing, it can mal-adjust the brake so that it will not release 100 %. That is, reversing with the brake partially engaged causes the brake to adjust up too tight. If the car does not easily roll backwards with just a little bit of pedal, stop, and recheck that you have fully released the brake. To do this, one resets the brake, then re-releases it.

Have the dealarship put the car on the lift, and reset the rear brakes. With the car on the lift, and the brake off, the wheels should be easy to spin. If not, have the rear brake adjusters reset. Then proper operation of the brake pedal will bring the brake setting into a correct amount of play.

You should not have trouble doing 70 mph. Hell, it should be hard to not do 70 mph in a Prius, due to its smoothness, and quiet nature.

You also need to use the parking brake. Using it resets the rear brake adjustment automatically. If its not properly adjusted, the amount of hydraulic slop in the system will be large, and this could make the switchover from electric to hydraulic braking jerky. Which might cause an unexpected reduction in braking power as one pulls in behind a stationary vehicle.
[/b]

The rear brakes on a U.S. Prius are not adjusted by the parking brake or by braking in reverse. They adjust automatically each time the brake pedal is depressed. It's a slick system. When the parking brake is applied, it presses on the far end of the adjuster to manually engage the brake pads, but that action also precludes any adjustment.

Here is a description and some photos of how it works

Tom

David Beale · 09-11-2007, 12:16 PM

I would first suspect it was very hot out and a lot of energy was being consumed by the A/C -and- your traction battery SOC was low. You do not have to "let off" the accelerator pedal just because the engine is screaming. It will take care of itself. If a lot of power is needed for the A/C and for accelerating the engine will scream (it will rev. up to 5000 RPM - some call this redline, but it's more like yellow line - it's used by the system but not exceeded).

Don't be afraid to make it rev. It's designed to do that. It will not damage anything. Use whatever throttle you need. The only time you would let off is in slippery conditions (heavy rain on oily roads, ice, snow). Even then, the only reason to let off is to ensure you don't force the car to save you. Because that also brings up a host of questions and concerns.

LisaM · 09-11-2007, 12:57 PM

You guys have been so great!! And no, I"'m not offended by anything- I'd be surprised if it wasn't ME that was doing something wrong...I've never had a new car, let alone the Prius, which is way out of my technical range of understanding...

SO I drove home last night and didn't feel anything wrong which made me feel SO much better....

I almost feel like I'm at the point of driving myself crazy...checking for wierd sounds, etc...I KNOW something was wrong when I dropped it off at the dealer last week, but they say its fine so maybe I'm just being paranoid. It was fine on the way to work this morning too....

You guys are sooo helpful- I'm learning a lot! Usually i just read the boards and don't post but I freaked out a bit after I felt the car being wierd...I didn't pay all this $ for a new car to be paranoid

I hope all's well...and maybe something was out of wack with the parking brake but now is ok, which is why it was wierd at some points...or maybe the AC?

OK i'm rambling! Thanks again!! If I feel something wrong again, I'll post it!

David Beale · 09-11-2007, 05:25 PM

Do read the two facing pages in the owners manual about strange sounds. It's pretty funny. Basically it says "anything you hear is normal".

The other way to interpret it is the Prius is not normal and doesn't sound that way! It has a different drive system and runs differently than most other cars on the road (except other HSD vehicles, such as the Camry hybrid and Altima hybrid).

09-11-2007, 12:16 PM	#17
David Beale Senior Member Join Date: Jul 2006 Location: Edmonton Alberta Posts: 1,525 My Car: 2007 Prius Package: B Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	I would first suspect it was very hot out and a lot of energy was being consumed by the A/C -and- your traction battery SOC was low. You do not have to "let off" the accelerator pedal just because the engine is screaming. It will take care of itself. If a lot of power is needed for the A/C and for accelerating the engine will scream (it will rev. up to 5000 RPM - some call this redline, but it's more like yellow line - it's used by the system but not exceeded). Don't be afraid to make it rev. It's designed to do that. It will not damage anything. Use whatever throttle you need. The only time you would let off is in slippery conditions (heavy rain on oily roads, ice, snow). Even then, the only reason to let off is to ensure you don't force the car to save you. Because that also brings up a host of questions and concerns. __________________ Edmonton Alberta "Pearl" is a 2007 Driftwood Pearl Prius.

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09-10-2007, 05:09 PM	#11
LisaM Join Date: Jul 2007 Posts: 7 My Car: Package: Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	Yeah I'm definitely in D....but it kinda seems like that- like if it were a manual, and I was in the wrong gear... Who knows...I'm going to have my husband drive it later and see what he thinks...then maybe drop it at the dealer AGAIN!!! Thanks

09-10-2007, 06:01 PM	#12
efusco Troll Slayer Join Date: Nov 2003 Location: Nixa, MO Posts: 13,993 My Car: 2004 Prius Package: #9 Nominated 1 Time in 1 Post TOTM Awards: 0 Friends: 23	make sure the parking brake isn't on.

09-10-2007, 06:03 PM	#13
richard schumacher nacreous lacquer Join Date: Mar 2004 Location: United States Posts: 4,087 My Car: 2004 Prius Package: #6 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	Don't be offended: is there any chance that the parking brake is engaged? This would not be the first time...

09-10-2007, 08:06 PM	#14
donee Senior Member Join Date: Aug 2005 Location: Chicagoland Posts: 1,502 My Car: 2006 Prius Package: #2 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	Hi LisaM, The parking brake is unusual. To be sure you have completely released it, you need to press down, the pull up with your left foot smoothly until your foot no longer is touching the pedal. If you stop anywhere along the release of the pedal, before the pedal is no longer touching your foot, you will have set some braking force. Additionally, some PC members have found that if the parking brake was not released, and the driver used the full torque of the motor during reversing, it can mal-adjust the brake so that it will not release 100 %. That is, reversing with the brake partially engaged causes the brake to adjust up too tight. If the car does not easily roll backwards with just a little bit of pedal, stop, and recheck that you have fully released the brake. To do this, one resets the brake, then re-releases it. Have the dealarship put the car on the lift, and reset the rear brakes. With the car on the lift, and the brake off, the wheels should be easy to spin. If not, have the rear brake adjusters reset. Then proper operation of the brake pedal will bring the brake setting into a correct amount of play. You should not have trouble doing 70 mph. Hell, it should be hard to not do 70 mph in a Prius, due to its smoothness, and quiet nature. You also need to use the parking brake. Using it resets the rear brake adjustment automatically. If its not properly adjusted, the amount of hydraulic slop in the system will be large, and this could make the switchover from electric to hydraulic braking jerky. Which might cause an unexpected reduction in braking power as one pulls in behind a stationary vehicle.

09-11-2007, 10:14 AM	#15
Sarge Senior Member Join Date: Nov 2005 Location: Mississauga, Ontario, Canada Posts: 555 My Car: 2006 Prius Package: C Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	Hmmm... I check back in here, and I agree with others that this no longer sounds normal. The parking brake does sound like a likely culprit. If you put the car in Drive or Reverse but then not touch the accelerator, does the car crawl as normal? This could be an easy indicator of a non-releasing parking brake...

09-11-2007, 12:57 PM	#18
LisaM Join Date: Jul 2007 Posts: 7 My Car: Package: Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	You guys have been so great!! And no, I"'m not offended by anything- I'd be surprised if it wasn't ME that was doing something wrong...I've never had a new car, let alone the Prius, which is way out of my technical range of understanding... SO I drove home last night and didn't feel anything wrong which made me feel SO much better.... I almost feel like I'm at the point of driving myself crazy...checking for wierd sounds, etc...I KNOW something was wrong when I dropped it off at the dealer last week, but they say its fine so maybe I'm just being paranoid. It was fine on the way to work this morning too.... You guys are sooo helpful- I'm learning a lot! Usually i just read the boards and don't post but I freaked out a bit after I felt the car being wierd...I didn't pay all this $ for a new car to be paranoid I hope all's well...and maybe something was out of wack with the parking brake but now is ok, which is why it was wierd at some points...or maybe the AC? OK i'm rambling! Thanks again!! If I feel something wrong again, I'll post it!

09-11-2007, 05:25 PM	#19
David Beale Senior Member Join Date: Jul 2006 Location: Edmonton Alberta Posts: 1,525 My Car: 2007 Prius Package: B Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	Do read the two facing pages in the owners manual about strange sounds. It's pretty funny. Basically it says "anything you hear is normal". The other way to interpret it is the Prius is not normal and doesn't sound that way! It has a different drive system and runs differently than most other cars on the road (except other HSD vehicles, such as the Camry hybrid and Altima hybrid).