hesitation on rapid acceleration

The same thing happened to me yesterday, passing another car on a two lane road, I was going downhill so I think the ICE must have been off. At 30 to 35 mph I moved into the other lane pushed my foot down and there just wasn't any power (not much anyway) then I think the ICE started and it was OK. About 1 or 2 second delay though, not a good feeling. Definately not due to traction control or VSC. I'll remember to put it in "B" next time. Maybe there is a use for the "B" mode after all. I'm going out and try to duplicate the problem tomorrow.

 

It happened to me once, too. I was following someone and had to pull out of a gas station and onto the interstate real quick. My Prius hesitated and I thought I might get hit by an oncoming 18 wheeler. Fortunately, this did not happen but I learned to be more patient with my car and wait until I have more than enough time to pull into traffic.

 

Gonna wake up this thread from the dead, because why not.

I was in a situation last night when coming off the "highway" onto a round about. Slowing down the 30 - 40 kph (15 - 25mph or whatever), all was clear and gave it less than half throttle, enough I thought to beat the lights down the road. I saw a 1 - 2 second lag and it was unacceptable to me. If it was a situation where I saw a gap and expected to be in it, it would've been so wrong. Thank god it was in the middle of night.

I'd say I blame pulse and glide technique, the one where you glide with no arrows on the screen. ... Or even if you were using the brake normally and then made a split second change of mind to accelerate for some reason. The car so misses on response when you floor after the engine is off (glide, regen, stop). When in motion, graduallly increasing the throttle to get the heretical mode helps it, but not good when you need to decelerate in the first place.

I've been told and definitely tried the "B mode" approach. I'm not too confident in it. I've experienced lag with it at junctions at the worst possible time. In the city, it's not unnerving. Drivers behind get too close and they need to see the brake lights to predict your speed. Letting the throttle off in B mode is too severe for most driving and most drivers would see you're dawdling and ready to do something stupid like a surprise U turn.

Anyways -

I've tried injector cleaners, increasing and decreasing tyre pressure, shaking and picking bits out of the airfilter before it needs changing. Sparkplugs are at least 20,000 miles in, coils are new too. Doubt engine or Transaxle oil would play a part.

There's really only two ways I've found effective to pre-load.

• Boy racer it. Only really when going straight and in dry conditions, just forcing the engine to idle with the brake pressed seems to give the most resposive, biting take off. Though, it looks dumb and I expect putting stress on the PSD. But it got me out of one really bad case of being "boxed in" and impressed a friend of mine who always ragged on our cars.

• The second one is the best one but only temporary. While moving and anticipating overtaking or anything that requires the response I need, I've been turning on the heater or demister at full blast and temp to force the engine to wake up. This works the most so far for me but it's short lived untill the engine reaches operating temperature.

I just hope by now a reliable solution has been found.

 

There is no solution the engine is off when your sitting and takes a second or so to spool up and get up to power.

And B mode is engine braking so have no idea why your using it in the city.
Designed to assist the car in braking coming down big hill.

Everyone has had that oh shit moment where you got yourself in bad spot and need instant power to get out if it. I won't do that again.

This car is not for everybody. Has poor off the low line instant acceleration but once it gets going it's pretty peppy. But very well made and dependable transportation and performs the mission it was made for perfectly.
I'm going on 10 years of ownership and it's been the best car I have ever owned dependable wise.
But if you beat on it to make it perform like a car it's not it will not last long.

 

I've found if I need to "go now!" the best performance is not to floor the "go" pedal, but only give it a controlled press to 1/2 - 3/4 initially then keep pressing/feathering further to keep the power up. It gets around that lag. I find it is better to work with the car, than against it.

offib, posts #18 and 19 of this thread are pretty much the best answers here, if you read the entire thread.

 

I was recommeneded B mode some time ago, so that the engine is spinning as a vac pump. I didn't see much improvement when I needed it against its downsides.

Maybe I should've just gone to the point at the end. I would agree with post #19 most that requires the engine to be on before demanding anything out of it. I've just seen too many situations like busy roundabouts and just mental stuff, all at low speeds, where I need something more effective with less room to work with. For me, the Prius's response is basically a god send, there's little I want to change about it. It's just these little momets...

And maybe I shouldn't say "floor it", it's not true. I definitely 1/2 and 3/4 throttle (when I mistakenly thought of flooring or gunning it) since I'm not going over 50km/h in the majority of situations, but I still get that engine lag at half throttle. This has been with the engine off. That's my main worry if it was something else like a dirty butterfly valve.
It's those rare moments of engine lag when I least expect it that I want to remove. Not the "Oh Shit" momets like a 18 wheeler barrelling behind you. More like defensive driving, right?

I found that turning on climate control at a high setting to turn on the ICE is, well my most effective way of avoiding that lag. Just to add in something incase someone reads this in 10 years and decides to try it. Pressing on the throttle like #19 says isn't totally for me mostly, not when driving off an off ramp at speed for 150 m rolling down towards a surprise-roundabout.

I'm not really interested in racing in - I'm much happier to glide and getting good mpg whereever possible. Especially when petrol here is somethig equivalet to $5.20 - 5.60 per US gallon.