Engine cycling rapidly/delayed rev

Cessna157 · 11-13-2007, 06:50 PM

2 items I have noticed Ruby doing occasionally:

1) Upon first start, as I power the system up, the ICE does its normal startup and warmup. It usually runs at idle as I back out of the driveway and accelerate. But as I gently accelerate, the ICE does not gradually join in the accel until reaching about 20MPH or so, then it jumps in revs rapidly. Has anyone else observed this delayed engine acceleration.

2) On very cold days (usually below freezing), with the heater on, the ICE will cycle on and off rapidly. I may pull up to a stop light, the ICE will stop for less than a second, start back up for 1-2 secs, then shut back down, and keep repeating this cycle. Anyone else expereiced this little cold weather quirk?

wb9tyj · 11-13-2007, 07:12 PM

<div class='quotetop'>QUOTE(Cessna157 @ Nov 13 2007, 07:50 PM) [snapback]539143[/snapback]</div>

Quote:

2 items I have noticed Ruby doing occasionally:

1) Upon first start, as I power the system up, the ICE does its normal startup and warmup. It usually runs at idle as I back out of the driveway and accelerate. But as I gently accelerate, the ICE does not gradually join in the accel until reaching about 20MPH or so, then it jumps in revs rapidly. Has anyone else observed this delayed engine acceleration.

2) On very cold days (usually below freezing), with the heater on, the ICE will cycle on and off rapidly. I may pull up to a stop light, the ICE will stop for less than a second, start back up for 1-2 secs, then shut back down, and keep repeating this cycle. Anyone else expereiced this little cold weather quirk?
[/b]

Its Normal...mine has been doing that for almost 4 years...

bestmapman · 11-13-2007, 07:41 PM

Hi from Cincinnati,

This seems normal. When the car first starts up it goes into Phase 1. In this phase the car wants to use the battery for acceleration.

Here is a description of the phases. Phases Description

Good to see another Cincinnati Priuschatter. Where did you purchase your Prius?

Cessna157 · 11-13-2007, 09:29 PM

<div class='quotetop'>QUOTE(bestmapman @ Nov 13 2007, 07:41 PM) [snapback]539169[/snapback]</div>

Quote:

Good to see another Cincinnati Priuschatter. Where did you purchase your Prius?
[/b]

This is my 2nd car purchased from Performance Toyota on Rt. 4 in Fairfield. I previously owned a 2000 Corolla. Performance is one of the best dealerships I've been to in terms of service, customer satisfaction, etc.

From what dealership does your Prius hail?

qbee42 · 11-13-2007, 11:23 PM

Before the engine warms up, the Prius tries to mostly use the electric motor (MG2) and keep the engine at low revs. If you push it, it will draw more power from the engine, and when it does, it really tachs up. Try to go easy on the gas until the engine warms up.

As for cycling on and off, this sounds like a situation where the state of charge (SOC) is high. When the battery SOC is overly high, the control system spins the engine without gas to burn off some of the excess charge. Driving down long hills can cause a high SOC, as well as the engine running a lot to keep the cabin warm.

Tom

9G-man · 11-14-2007, 02:29 AM

Good to know! I've experience this since it's cooled down lately, the rapid shut-down/restart after having run only briefly.

bestmapman · 11-14-2007, 09:15 AM

<div class='quotetop'>QUOTE(Cessna157 @ Nov 13 2007, 09:29 PM) [snapback]539212[/snapback]</div>

Quote:

This is my 2nd car purchased from Performance Toyota on Rt. 4 in Fairfield. I previously owned a 2000 Corolla. Performance is one of the best dealerships I've been to in terms of service, customer satisfaction, etc.

From what dealership does your Prius hail?
[/b]

Beechmont Toyota. I've had it sence March.

11-13-2007, 11:23 PM	#5
qbee42 Senior Member Join Date: Mar 2006 Location: Northern Michigan Posts: 4,791 My Car: 2006 Prius Package: #7 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 5	Before the engine warms up, the Prius tries to mostly use the electric motor (MG2) and keep the engine at low revs. If you push it, it will draw more power from the engine, and when it does, it really tachs up. Try to go easy on the gas until the engine warms up. As for cycling on and off, this sounds like a situation where the state of charge (SOC) is high. When the battery SOC is overly high, the control system spins the engine without gas to burn off some of the excess charge. Driving down long hills can cause a high SOC, as well as the engine running a lot to keep the cabin warm. Tom __________________ *Black* 2006 package #7 Northern Michigan

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11-13-2007, 06:50 PM	#1
Cessna157 Junior Member Join Date: Oct 2006 Location: Cincinnati, Ohio (CVG) Posts: 12 My Car: Package: Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	2 items I have noticed Ruby doing occasionally: 1) Upon first start, as I power the system up, the ICE does its normal startup and warmup. It usually runs at idle as I back out of the driveway and accelerate. But as I gently accelerate, the ICE does not gradually join in the accel until reaching about 20MPH or so, then it jumps in revs rapidly. Has anyone else observed this delayed engine acceleration. 2) On very cold days (usually below freezing), with the heater on, the ICE will cycle on and off rapidly. I may pull up to a stop light, the ICE will stop for less than a second, start back up for 1-2 secs, then shut back down, and keep repeating this cycle. Anyone else expereiced this little cold weather quirk?

11-13-2007, 07:41 PM	#3
bestmapman "Dream" Prius Join Date: Apr 2007 Location: Cincinnati, KY Posts: 667 My Car: 2007 Prius Package: #2 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	Hi from Cincinnati, This seems normal. When the car first starts up it goes into Phase 1. In this phase the car wants to use the battery for acceleration. Here is a description of the phases. Phases Description Good to see another Cincinnati Priuschatter. Where did you purchase your Prius?

11-14-2007, 02:29 AM	#6
9G-man Senior Member Join Date: Jul 2005 Location: Atlanta, GA Posts: 619 My Car: 2007 Prius Package: #5 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	Good to know! I've experience this since it's cooled down lately, the rapid shut-down/restart after having run only briefly.