problem with my 2004 prius

The other night I was driving home from the State Fair (about a 1 hour drive) and my Prius started acting really weird. Every time I let up on the accelerator (when I should go into charge mode), it sounded like the engine was revving. It sounded like a gasoline engine that was put in low gear at a high speed. It was also very clunky. Has anyone else had this problem? I stopped the car to make sure that I hadn't accidentally put it in "B" gear by mistake, but this didn't have any effect. The next morning when I started the car again it was back to normal and has been normal ever since. I'm taking it in on Monday to be checked out, but I don't think they will find anything unless it happens again. Has anyone else had this problem? Any ideas about what may be causing it? I thought it could either be a problem with the transmission or maybe maybe the gas engine isn't turning off when it should?

 

Thanks for the info--I knew there was a different method of controlling the Prius engine, but I wasn't sure how it worked. I forgot to mention that my problem happened just a couple of days after my 5000 mi. checkup. When I picked up my car from the dealer, the battery was completely discharged--no lines showed on the battery window. Wonder if they could have messed something up with the computers then???
Just wanted to add that they changed my oil at the same time.

 

Thanks to everyone for your input. I got to thinking and this is actually the second time the dealer returned it to me with a discharged battery. The first time was when I took it in for the recall to be reprogrammed. I think you are right about the air-conditioning--it was turned up to max cool when I got it back and I had to reprogram to a normal driving temp. Is it worth making a formal complaint about the previous discharges or is it not likely to have much effect on the life of my battery? The battery has never been that low when I have had it, and that includes not driving it for a period of 10 days when I was out of town.

I am hoping that you are right and that this was just a case of the battery overcharging. The problem is that I have driven the same route between Ithaca and Syracuse at least five times and it never happened before.

 

I took my car in today and they didn't find any errors on the computer, so they have no idea why it was grinding away on my trip from Syracuse. They also denied that there was any way to run the traction battery down by running the air conditioner, radio, lights, etc. When I went to pick up my car I handed them a printed copy of your comments about the IG On mode (as well as a similar message on somebody else's thread on the other Prius website) and handed them to the service writer. He gave them to the service manager who is going to "research" this with Toyota. So we will see. I thank you all for the help--I've never felt so powerful in the face of a dismissive service tech before!!!

 

Re: problem with my 2004 prius (UPDATE: it died)

Well, my Prius died tonight. :cussing: I went to the park and things were fine; traction battery with a charge in the blue range (ca. 75%) last time I looked on the way there. Downhill prior to parking, so probably fully charged. Walked the dog for half an hour, came back and nothing lights up on the dash except the malfunction light. No headlights, no windows, no power steering. The computer screen comes up, battery is completely white. Gas engine will start up and run, but no power except from the 12 v. Called Toyota Help line, but couldn't get a tow truck for 2 hours so went home with friends. Will have it towed tomorrow. So did my traction battery die or is it a computer problem?

 

Re: headlights. You're right I should have said no headlights when I hit the power button--I usually leave them on so they come on automatically when I start up the car. In this case, I had to turn the headlight control to the off position and then on again manually to get them to work. So it's a computer problem?

 

The dealer finally called. The tech doesn't know for sure what's going on and can't work on it again until Thursday. The service writer said that it looked like the power source for the ECU relays was not working, but they aren't sure why. Anybody know what that means? Also, no estimate on how long they will have my car beyond Thursday.

 

Well, I got my car back on Monday (they had it a week). The service tech said that the IG-1 relay was bad and they had to replace it. I still have a number of questions about the whole experience:
1. Were all the problems I had earlier (see beginning of this thread) with my battery being discharged related to this problem? According to the tech, very likely. He also claims the battery didn't actually discharge, it was only the display showing it that way because of electrical/communication problems. However, my car had the same sluggish behavior described by others when their traction batteries were low, and it did eventually charge both times. So--I am not entirely convinced.
2. If it was a relay problem, why did my battery show a discharge both times I took it in for service and not at other times? Why did I experience problems two days after the 5,000 mi service?
3. If the two problems (discharge/relay) are related, why didn't they find the bad relay when they purportedly scanned the computer in my car before the actual breakdown happened?

So far, this service tech has told me the following:
1. It is impossible to discharge the traction battery without running down the 12v battery first. Wrong, according to people on this board.
2. You cannot run the air-conditioner in IG-On mode. False, by testing my own car.
3. This time he told me "The computer won't let you discharge the traction battery--it will prevent it from happening."

So, I'm still not sure if I have one problem or two and I'm afraid to drive my car very far from home since I'm not sure how reliable it is. Does any of this make sense to anybody? Could all of this been caused by installing the wrong fix for my recall? In retrospect, it seems that my problems started when I took it in for the ECU reprogramming.

 

I would love to go to another dealer. Unfortunately, the nearest other dealer is 60 mi away in either Syracuse or Binghamton. Since my car was towed in, I didn't have much choice.