I have searched this and other forums and not found anyone else that encountered this issue.....2010 with 120k miles, suddenly began making drive line noise when under power from ICE. Basically, there is a rumble coning from the drive line, and if you accelerate a bit, there is an occasional thump. When cruising under battery power, everything is quiet. I slowly and carefully drove it to my favorite repair shop, about 5 miles, and await his investigation, but he has never worked on a Prius. At first, I thought it might be a bad CV joint, but that wouldn't seem to be consistent to no noise while running on battery. Anyone else encountered this type of problem?
Welcome to Prius Chat . The noise only occurs when the engine is running? At 120 k miles your Prius is due for spark plugs. Has it thrown any codes? Have you owned it since new? I see your location as Avoca, as in Northeast Pennsylvania?
You can pretty much eliminate a driveline issue because it only does it under ICE power. Power train is another animal. I agree with Raytheeagle that you need to start with replacing the plugs. Then I would consider the EGR system as the next place to tender some maintenance. At that mileage the EGR system (and most likely) is clogged up with carbon deposites.
I have obtained the plugs, just waiting for spare time and decent weather to install them. The problem isn't a miss in the ICE, it is definitely coming from the driveline. I originally suspected CV joints, but it doesn't make sense to me that it would only occur when the ICE is powering the car. I have since watched some of the excellent videos available and am pretty suspicious of a transaxle problem. Should have some feedback from my local repair shop today, at least with regard to eliminating the CV joints as a possibility. Yes, Avoca as in NE PA.
One way to check if it is an ICE issue is to put the Prius into "Maintenance mode ". This will run the engine while the car is stationary so you can inspect the engine bay. This would be a way to prove if the noise occurs while the ICE is running and is not a driveline issue. In the Gen3 Maintenance and troubleshooting section, there is a sticky thread for maintenance videos. #11 is the engine coolant drain and fill, but at the end of the video it has the method for putting the car into maintenance mode. It's a chicken dance, but it will display on the HSI screen when it enters and the ICE will run at idle. How is the oil level? Does your Prius consume any oil between oil changes? I am originally from the Harvey's Lake area, so familiar with the area. I'll be flying into the Wilkes-Barre / Scranton international airport tomorrow morning to visit my folks. Good luck and keep us posted .
Update and Conclusion! I had the car at a friend's repair shock to check external things, especially the CV joints. He didn't find anything. I decided to take the leap and made an appointment at the Toyota dealer where I purchased the car - just 3 miles away. SURPRISE! The problem was a rotted heat shield which had come partially loose and was rubbing around underneath. Decided to spring for a transaxle fluid change while the car was there - OUCH! - $120! And they wanted me to sign up for engine and inverter coolant changes @ $190 EACH! I passed, but have ordered the Toyota coolant on line and will handle these jobs sometime in the next 2 weeks. Thanks to all for feedback and comments. CRISIS AVERTED!!!!
Glad this worked out for you . $120 for the trans change seems in line. The coolant changes seem high though . Here's a link to videos that are very helpful to perform maintenance on the Gen3 Prius (including the coolant changes you are about to have done): Nutz About Bolts Prius Maintenance Videos Did you see the condition of the trans fluid or did they mention anything? Was that the first time you had it changed?
$120 for transaxle fluid change is meh... The fluid, 4 quarts of Toyota ATF WS (3.5~ used) plus 2 washers (if they even changed) is about $40 retail. The labour with a full lift is trivial: about 1/2 hour, similar to oil change. $80 would be a good price.
