Acceleration problem

don't know the cause, but it is under warranty. only problem is, if there are no codes, and it's running fine now, they won't know what to fix.

 

Did you knock it into neutral on accident by any chance? I once did this when I was switching from "B" to "D" at the bottom of a deep slope. I was waiting until I got to the bottom of the hill to switch to "D" but forgot that holding to the left will put the car in N.

Although if this happens again I would take it to the shop. That's a little freaky to experience.

 

If there were no warnings, error codes/lights, or anything, then my next guess would be you had a condition preventing the battery from assisting and were on engine power alone.

Did you have 1 bar on the MFD?
Was the back fan running?
Was it hot outside?
Were you previously doing a lot of regenerative braking (stop & go, or long downhills)?
Were you driving aggressively with speeding up and then slowing down with friction brakes?

 

2k1Toaster, this happened to me today and I would like to know why. I don't get any acceleration when going uphill, it starts slowing down from 60mph - 50mph, and I'm sure further if the hill was longer. The battery was showing depleted at this point but even when I floor the pedal it's still decelerating at that rate, flooring the pedal does nothing to the engine, no noise difference, etc. I just bought this car used, final sale

Also, I get a warning randomly that says "Problem" on the screen, with a warning symbol. But trying to pull codes with an older diagnostic tool did not reveal anything. I'm going to have jiffy lube pull them, maybe their updated tools are better.

There is no check engine light.

 

If Jiffy Lube also can't pull codes, I would try the Toyota dealer.

 

I just bought this car the day before yesterday, I already tested the 12v battery, and it pulled no DTC codes. According to the law I believe I have two full days to return it (even though he sold it as-is to me). He never disclosed anything about a 2 day warranty, which according to a yahoo article is a must IN WRITING.

Google "ffvr35" and "California laws used car buyer".

So when going uphill, as soon as the battery is depleted (1 bar) the 2007 prius loses 80% power and it starts slowing down RAPIDLY, from 65mph down to about 45-50mph with the pedal floored. It is very alarming, not to mention dangerous. I have a feeling it's the main traction battery...I'm going to attempt to return it to the seller (sold it with his dealer license), but he seems like a very shady man so this will get interesting...stay tuned...

 

What is "uphill"? To someone from the plains, uphill could be 50ft over a mile. For me, we call the 2000ft elevation change up the Rocky Mountain a "hill".

If you are going up a mountain, it is normal to lose speed. If it gets to 1bar, then essentially you have no power. The trick is constant power, NOT constant speed. If you are going up the mountain pass, floor it and leave it floored. It doesn't lose 80% of the power. But it does lose 26% power. The engine is 73hp and the traction battery can supply 26hp. If you are at 1 bar and no bars flowing into the battery (charging the battery), then almost all the 73hp of the engine in going to the wheels and 0 to/from the battery.

You just bought a 2007, so I am guessing you have around 100K miles on it. At this point the spark plugs should be replaced. Bad plugs can make a problem with power. Also if it was a dealer, your tire pressures are artificially low in the low 30's PSI. Inflate those up to 45psi. The Prius to me feels sluggish when underinflated like that, but people like it cushy apparently.

The big thing, is that you have the "Problem!" message on the MFD. These generally don't just appear without the previous owner knowing about it. You need to pull the codes. The Prius is not your average backyard mechanic vehicle. You need to either buy a real instrument yourself, or go to a sop that knows what they are doing. Pull the codes and post them. If the car has never had the warranty recall done for the inverter coolant pump, now is the time to do it. It is still 100% free from any Toyota dealership. Easy check, open the inverter coolant reservoir with the car in READY. You should see turbulence in the tank. If not, the inverter is not being cooled and then you will get to 1bar easily and the car will throttle down the battery power because it is too hot. Do you ever hear the traction battery fan turn on? (Back passenger side seat vent).

I think you are jumping the gun trying to return the car so fast. If you paid over retail price, then I would be upset too. But this is a used vehicle and you have no idea if the previous owner even did the basic maintenance and recall work. Used cars are a gamble for anyone, and you might have one that requires serious work, or one that needs the free recall done and be good.

 

When I first heard about the runaway Prius incident in San Diego in 2010 and the driver was James Sikes, a financial trouble real estate agent, I just laughed and said to myself: "This guy was nuts!!! He picked a wrong car to extort the Toyoyta company." Well... that was 3 years ago... And now, I own a brand new 2013 Prius myself and after a few oddly behavior my Prius has exhibited, I begin to believe the runaway Prius incident in San Diego was not a scheme or a hoax at all.

My Prius has only 4K miles on it and just went through the first 5K-mile maintenance last Saturday. So far there has been three glitches that I've experienced with:

- A few months ago, my car refused to start twice, consecutively. The triangle master warning light just kept flashing as I pushed the start button while my foot firmly pressed on the brake pedal. I had to get out of the car, reentered it and then I succesfully started my car the third time.

- A couple weeks ago, I drove my family to a shoping mall. The ICE refused to turn off by itself at the 5 red lights which I had to stop and waited for a long time. It was a beautiful, sunny and warm/cool afternnoon. The car battery's indicator showed it was almost full. No head lights, AC or heat or anything that would force the engine running were on. Magically, the car ran normally on the way back from the shopping mall.

- I live in the Seattle area and I have to use the downhill-assist control brake quite often due to the hilly roads. Last week, my car refused to activate that function when I was at a steep hill intersection. My Prius once again ran normally after I reached my destination and turned it off.

The story about James Sikes (JS) incident made me wonder why the cop who assisted JS to stop his car insisted that JS did not fake it. He saw smoke and burnt smell came from the Prius's brakes after it stopped...

I have no doubt that my Prius will last a long time but its computers are not reliable. Once in a while there will be a glitch which make the car behaves oddly. So far, there is nothing bad enough to put me and my family in danger. Each incident is unique and non repeatable. In case of JS, Toyota just flatly denies anything wrong with the Prius or its design. The media just turned to JS and portrayed him as a bad guy...

References:
Toyota dismisses James Sikes' account of runaway Prius, claims tests prove car was running fine - NY Daily News
Toyota Hybrid Horror Hoax - Forbes

 

I see several problems with your reasoning here ---

The car has multiple criteria that must be met before the ICE will turn off in this situation, and your description isn't sufficient to cover the well-known items. Therefore I cannot take this as any evidence of unreliable computers.

What do you mean by 'downhill-assist control brake'?

B-mode engine braking? Cruise control used downhill as a regenerative brake? Brake Assist during panic braking? Hill Start Assist for uphill starts? Something else? Lacking some better description, I cannot take this as any evidence of unreliable computers.

From your link:

I.e. he purposely abused the brakes and seriously overheated them. The smoke and burnt smell is absolutely no surprise. This is not evidence of unreliable computers.

As for your car's refusal to start several times, please keep us informed of future failure patterns. Many of us suffered repeated failures to start when the car was new to us, but these failures declined rapidly as we gained experience. This pattern is highly suggestive of 'pilot error' that diminishes with experience. But I don't recall seeing the master warning light, so cannot have confidence that your incidents are from the same cause as mine.

 

The "failure to start" is common when the key is not detected. If it gets between my body and cell phone, the car wont start because the RF is sufficiently blocked. Even when it is the only thing in my pocket and the battery is pretty low, it requires jiggling to get it to respond. Then it is time for a new $1 battery.

 

ICE running longer & car not powering down are symptoms of a weak 12v battery. The engine runs longer trying to charge a bad battery. I've only been able to get 3+ years out of the OEM battery. The Toyota battery I bought from a dealer for my 2006 lasted a couple months & was replaced under warranty.

Weak fob batteries are the most likely culprit for "car won't start". The brake pedal may not be fully depressed or there may be a problem with the switch.

The officer reported seeing Sikes' brake lights illuminate a number of times. Did Sikes intentionally burn out the brakes to get out of his lease, or was he trying to extort money from Toyota, or did he have another agenda? I don't know as he was pretty much swept under the rug.

If the Prius computers weren't reliable this site would be clogged with complaints. Sorry, I don't buy the conclusion.