2007 "slips clutch" as motor runs but does not power wheels, restart car, and it works again

Yes your HV battery is about depleted It's very old etc My car did this when my battery HV battery was 13 years old as soon as I replaced it all of that went away That's your gas engine and your electric motors not able to sync up and do the right things because the battery doesn't have enough AH to keep the electric motor up when you're driving so you'll step on the gas and it'll sound like the clutch is slipping but there is no clutch. I know it's something you probably don't want to hear but sorry.

 

By any chance, is it going into Neutral? By any means, whether pilot error, electrical glitch, or mechanical problem (e.g. broken spring) in the gear shift lever assembly.

Problems with the gear shift assembly haven't been all that rare.

 

HI Doug, I'm an hour's drive south of you... You're welcome to get in touch if you need more help.

Only similar thing to this that is a known problem would be the traction control system, but that has a dash light that blinks when the traction control is cutting off your power to protect the drivetrain from the torque of the electric motor.

Another thought is that the VVT solenoid that controls valves is a bit slow and sometimes when pulling into traffic and stepping on the gas it will take a 1/2 second for engine to respond, which is stressful. But you can upgrade to a higher quality VVT that eliminates most of the lag time. It's a very easy part to swap out: https://www.redbullet.net/

 

Hi Doug,

I have, along with many others, the exact problem you describe.

The only reliable way to diagnose these highly complex computerized cars is to “read the codes and subcodes”.

Toyota has a product called Techstream which you can use to do this. You can buy a hacked, never expiring, version of Techstream on eBay and Amazon under mini VCI cable.

There are other options but this will work to let you read the codes. This will lead you directly to the faults. Anything else is just guesswork.

 

That's actually about right for inverter removal on a generation 2 3 bolts are holding it down three clamps including the little bleed line and however many screws going around the cover the six screws holding down the two main plugs with their two hold down screws for each plug if you're using an electric nut driver that's about right 20 minutes inverters dropped on your foot or wherever you said it just did it yesterday. And if I can just blast the bolts out and let them fall like at the junkyard knock off another minute or two. But this is not how you work on your own car That's why has 1500 in the backyard It's a junkyard.

 

Sounds to me more like an inverter temperature issue. A big clue is that the problem solves itself after the car is off for a bit. The inverter cools fairly quickly when it's off. The only way to know for sure is getting a proper diagnosis.

The inverter cooling water pump is a relatively inexpensive DIY job.

 

Are there any indicator lights showing on the dash, either before or after the engine starts to rev like that?

 

Not me, I live in the opposite direction.

 

@TMR-JWAP has nailed it. Again. It's easy to check the inverter pump and I'm about 99.99999% sure that's what it is. None of the other suggestions make any sense.

Two things to do. One is to open the cap on the inverter coolant reservoir and look for a swirling motion the coolant. It should be pretty obvious if it's working right. The car has to be in READY, but it doesn't matter if the engine is running or not.

The other thing to try is to just listen for the pump when in READY mode. You should be able to hear it or feel the vibration of the pump when you touch the inverter coolant hose coming from the pump.

To replace it, loosen the left side of the bumper cover and remove the driver's side headlight. It's right there.

 

You've got the idea. Best to eliminate that NAPA guy as a middleman, just read the codes yourself with a good scan tool and tell us what they are. The car is trying to say what the issue is.

Techstream is a good option, and you can review this thread to see some other options that are able to read all the codes from a Prius (which, of course, is the main thing you want):

Gen2 OBD2 app review | PriusChat

 

I have to look at this removing the headlight business that to me seems like something I never want to do I've done it twice disassembling a car not putting it back together to get the headlights out to save You have to undo the part of the front bumper cover etc usually when I've changed my inverter pump my long needle nose angled pliers reach down and undo the hoses I'm not worried about saving the coolant and then my 10 mm wrench reaches down there and I unbolt the pump or the three gold bolts holding the pump to the bracket I can move the pump a little bit over now my needle nose pliers undoes the plug. And then I just pull the pump up right past the inverter the headlight and the core support and it's wing the frame of the car in other words and I'm holding it It just seems to me pulling the bumper cover out of those plastic clips that grab onto the bumper cover that don't like to go back in and then pulling that forward and then undoing the bolts on the headlight removing it oh yeah I got plenty of room to work on the inverter pump now but the other way at the point I get the headlight out I'm already put in the other one back in and almost finished but it is an interesting way to do it I guess. The first time I went to take the headlights off of a HID 05 Prius I was quite taken aback that these metal brackets on the bottom of the headlight slid into the front bumper cover. And I can never get those plastic clips to receive the bumper cover once I've taken it out usually I take I have a caulking gun that has urethane in it the black stuff like you put the windshields in with I run a beat of that into that plastic clip business let it set a minute then push the bumper cover into that and put a piece of tape on it for about 4 hours now the next time you go to pull it out you might rip the front bumper cover tabs off but usually when I'm ripping the front bumper cover off I'm changing those plastic mounts and probably getting a new bumper cover that's why it's coming off.

 

PLus 1 on invertor pump. Look in cap for your pink coolant to me moving around when the car is in READY mode. OEM Pumps last about 100K cost $165 at the dealer...make sure you get an OEM pumps more than half the pumps on Amazon are FAKE Spark plugs too. Doing the job is not hard but you don't want to do it more than every 100K....and start saving $2500 for a NEW Battery and have it run for another 250K

 

So when my hybrid battery was dead confirmed dead or pretty much not doing anything My gas engine was running all the time 37/39 mi to the gallon Right before it got that bad like when I initially got the car and was driving away from where I bought it I went to wamp down on the gas pedal And the engine RPMs would go up I could literally hear them and I wasn't going anywhere or not moving ahead of what I was already doing I would back off the gas and go down much lighter and the car would accelerate right on up to 65 70 mile an hour. I thought that was funny because of no clutch and nothing to slip and what have you didn't really think about it. But during the time of about 4 months maybe six I was able to do this a lot like I'd be in town and step down on the gas doing 3540 miles an hour trying to get to 60 and all of a sudden the car would rev with wild abandonment make you take your foot off the gas and then go back down a little slower right up to speed. I just thought it was the two power devices the electric motor and the ice engine we're not able to compliment each other correctly because the electric motor was essentially running out of juice before it hardly got started because of the poor battery so I just figured the ice engine was trying to overtake if you will the electric motor and that's certainly what it sounded like. The minute the battery was replaced now I can't make this happen.

 

If you can get to it with the headlight in place, good on ya!

In the shop, we always remove the headlight after loosening the the bumper cover. The whole job start to end is usually about 10-12 minutes.