I'm in Southern California. I bought a 2001 Prius with 120,000 miles on it in November 2016; like new interior and very good exterior, too. It had serious problems within the week after I bought it but that's another story for now. I had the inverter coolant pump replaced on Saturday. When I got it back and drove it, the mileage was 10 mpg after it had been driven for 15 miles. Now it is 21.4 MPG after driving for 60 miles. The reason I had the inverter coolant pump repaired is that the Triangle light and check engine light went on, so I went to the repair shop right away. They "bled the lines" (4th time) and told me to drive it home and bring it back in two days and said it was fine to drive. I got about two blocks from the shop in heavy traffic and the display went nuts, and the car quit and wouldn't move in the middle lane. Couldn't even get it to the curb. Plus it was 95 degrees. So a tow truck got it back to the shop and they replaced the inverter coolant pump. I asked the shop owner if the 12V battery would be okay. He said they charged it and I asked if it would hold a charge; he said it would be fine. So I'm wondering if the MPG would be accurate if the display started from zero after the battery had been disconnected, and if it would be normal for the car to show only 21.4 MPG after 60 miles? As I drove it on the freeway after getting it from the shop I could see the real time display often at 100 MPG. I'm still not that familiar with all the little ins and outs of the car. Before the inverter coolant pump repair it usually showed 38 MPG in city driving. I've had a ton of trouble with it and am hoping this doesn't mean more serious issues. Already replaced the big battery and the Inverter and am having serious trust issues with the car. Thanks for reading. Hope there are some math whizzes here Milan
This is not a math issue, this is an issue with a 16 year old car. Your troubles will continue and if you can't fix this car yourself, I advise you to sell it
I personally believe that 120,000 miles is a young Prius. Even if it is a 2001. Now that you've replaced the big expensive high voltage battery I really see no reason that you should not be able to get 300,000 miles, without further issue. My doctor and my older brother both have 1st generation Prius's. My brother an engineer, still owns his. My doctor, unfortunately, never understood the technology and gifted his to his nephew who traded it in for $800. I say stick with it, you've had a rough patch and are nearly through it. The rewards will be years trouble-free driving though the gas mileage will be 40mpg. iPhone ?
For the MPG display, the 10 mpg after 15 miles is the problem. Starting from that, 21.4 at 60 is not any additional problem. Reset the mpg gauge now, so that you are starting fresh. Without a reset, that initial 1015 reading will mess up all subsequent readings.
10 MPG @ 15 miles = 1.5 gallons. 21.4 MPG @ 60 miles = 2.8 gallons. Therefore, in the last 45 miles you used 1.3 gallons = 34.6 MPG. Not ideal but you stated 38 MPG before repair so it looks reasonable to me. I would assume the initial low reading would be from the engine running during the bleed of the inverter pump replacement. Assuming again, that first 15 miles @ 34.6 MPG actually burned 0.4 gallons which means they used over a gallon bleeding the coolant. Seems high to me but not impossible. I would like to think you are going to be ok from here but you can reset the gauge and check from a true zero use point.
Sorry it's been a while; I went through a lot with the car after this, as you said could happen. It's been pretty good until a few days ago when someone hit me.
Thank you so much for replying. Sorry I didn't get back to the forum to reply right after you posted. It turned out that the inverter had a problem as well. I bought the car from the shop that replaced the expensive high voltage battery, and they replaced both the high voltage battery with an after market battery with a 4 year warranty, this is the second one. After that, I did have to replace the 12V battery. Since then the car has been fine with no problems, until I was hit a few days ago and the right rear wheel is now bent. It still runs nicely, it just rolls funny now
Sorry to you also for not replying right after you posted; you were exactly right, the inverter was no good. The shop replaced the inverter for free along with the high voltage battery as I mentioned above and other than replacing the 12V I've had no problems with it until a few days ago. Thank you, you know what you're doing!
I really appreciate the math, it gave me optimism when I was really upset about the car. As I mentioned replying to the other replies, the car did need not only a new inverter pump but a new inverter and new high voltage battery, then a new 12V, but since then the car has been trouble free. Thank you again, Litehold
