My 04 Prius with 24k miles on it has started to make this noise since this past Saturday. Whenever I start my Prius after it's been parked for a while, whether it's outside or in our garage, the engine seems to make extra loud noise. It comes on and goes off a few times and then it stops making that noise. At first I thought it was related to the fact that the battery was full, but I've seen it happen a few times when the battery wasn't full as well. Anyway, it's a new noise that wasn't there before. The outside temperature has dropped to about 37 in the mornings/evenings. But I didn't have this problem last year when it got this cold. Has anybody had this problem? I'm having it looked at by the dealer next Tuesday, but when I described it to the technician he had no idea what was going on either.
Take a look at this, might be your problem too. http://priuschat.com/Hot-Coolant-Transfer-...t-2-t13284.html
That could be it. I'll have to ask about that on Tuesday. But it's not squealing. It's definitely louder than normal.
The hot coolant transfer pump will run year round depending on the temperature differential between the coolant in the block and the coolant in the tank. It is part of the emissions system in that storing hot coolant and then putting that hot coolant back into the engine upon cold start will shorten warm up time and help reduce cold start emissions, which are probably the worst a modern car can produce. Since you first purchased the car you should have been hearing a hum almost every time you started the vehicle from after long rest period (overnight, a few hours at work, etc) from the front drivers side of the vehicle. You should also have been hearing this hum almost every time you shut the car down as the vehicle would then take the hottest coolant and move it into the tank.
Yes, I usually hear the hum. But this is way louder than the humming that it made previously and it's really annoying. It's more of a scraping sound. It only makes the noise when starting the car, not when switching it off. When I start the car, it makes that sound for about 2 seconds, then it goes away for 2 seconds, and this repeats for 4 or 5 times before it goes away altogether.
I think eklabbers is describing what I've been hearing, except that it doesn't repeat. Check your coolant level and see what the dealer says. I took mine in and the Prius technician noted my lower than normal coolant level and said he'll do the TSB while the Prius is in the shop.
[Broken External Image]:http://img.photobucket.com/albums/v739/indydoug/cold.jpg I've noticed a sound coming from the ICE during cold starts lately. It goes away after a minute. Can't wait until the temp warms up so I can make sure the sound is cold-weather related and not a sign of a mechanical problem.
I took the car to the dealer for the software update (and to get a new rubber pad for my foot brake, since that came off every time). I explained the noise, and the guy that helped me told me it was probably just wear on the parts, combined with the cold starts. But when I came to pick it up in the evening, they said they had just located the problem. Apparently my A/C isn't working. They didn't have time to look at it then, plus they needed to call Toyota to ask for help and order parts, so I'm taking it back in on Friday and will leave it there until Monday/Tuesday. I noticed that the sound went away as I turned the fan off on the climate menu. I'm glad it's not affecting any crucial part of the car, but hopefully they can fix it. Good thing that the car is still under warranty.
Well, here's an update. They replaced the A/C inverter (or something of that nature) and that didn't fix the problem. That took a while bc we had an ice storm on Monday and so they didn't get the part until Tuesday, and for some reason they couldn't work on it on Wednesday and Thursday. So now they're ordering a new A/C compressor. When searching on the forum I found one other post of an '04 Prius that had the compressor replaced. I hope they can get it done, bc we're leaving Tuesday evening to go on a weeklong vacation and I'd like to have my car back before we leave (even though we are flying). I've been driving this 2005 Corolla as a loaner and it's driving me crazy. You have to put the key in the ignition. How old fashioned. And it locks the doors everytime I get in the car, so when I step out and try to get my bags from the back seat, the back door is locked. The gas tank is already half empty and I've only driven for about 135 miles. I keep grabbing for the joystick to shift to reverse and drive, and my thumbs want to push buttons to change radio channels, adjust the volume or the heat
prius owners in loaner cars never fare well :lol: glad to hear they're sorting it out- did they cite the reason for the failure? i don't remember which component, but one component of the a/c is susceptible to road debris and can get all messed up. good thing you don't really need the a/c this time of year
They didn't know what caused it to fail. I went in because I had to have the ECU update done, and I noticed the new noise. They didn't know what it was, but concluded it had to do with the A/C not working. At least it's still under warranty, so it doesn't cost me anything.
