First off - I'm really sorry that my first post is a request for help. I was driving home this evening; and noticed a higher than normal degree of rolling resistance/drag on the car; similar to what you'd expect with a flat or near flat tire. I tried to get the car up to speed (45-55mph); however the throttle resistance became even greater. Further when I got up to 55+ mph; the transmission (or whatever it is we have) would seem to upshift resulting in no ability to accelerate; and a low drone sound. I did notice that even at low speeds there was a good amount of rolling resistance with even very soft acceleration; resulting in the miles/gallon indicator down around 20-22mpg. A few additional bits of information: -I did drive the car into the office around 12 hours earlier, with no problems -There has been a bit of a rattling sound coming from under the car which I suspect was a loose heat shield -the car has 145K on it -I checked oil; and it looked OK, last change was +/-4000miles ago -I didn't notice any drips from under the car -original batteries -no warning lights I'm going to take the car in tomorrow morning to my mechanic; however was hoping to get a few pro tips on what it may be, prior to walking in blind. Thanks in advance!
Welcome to Prius Chat . You say it felt like a flat tire, so what was the pressure of each and we’re there any that were low? Any dragging brake pads (are the center of the rims warm)? Any change in gas or octane? Any recent maintenance or damage to your Prius? Good luck and keep us posted .
Thanks @Raytheeagle; pressure in tires looked good - I didn't test them, however based a solid eyeballing, nothing out of the ordinary. Same old Costco gas; Not sure about dragging brake pads; however I doubt it - there was a solid rattling when I got up to 50-55 mph; and the tranny up shifted; both which seem to be un-related to brakes. No recent maintenance aside from the oil change; an no new damage (door dings etc).
This has snagged me on two past cars (shop repair error on one, repeated sticking pads from corrosion on the other), so is something I'm quite watchful for now.
Catalytic converters can clog and severely limit the power of the ICE. Maybe the rattling was a rusted out portion of the cat coming loose and blocking the rest.
Just to clarify: does that include original 12 volt battery? If so, wouldn't hurt to replace that. I'd second the various brake suspicions. And the suggestion to feel the rims immediately after a drive; see if any feel particularly warm.
The above are likely culprits, but could I add one more. When my wife hung a bag over the right side of the gearshift lever in our Gen 3 hatchback, that caused it to slide right and engage “B” or braking mode , during which I experiences abnormally low mpg, abnormally high resistance to acceleration, and abnormally quick braking with I let off on the throttle. You seem to have some of those symptoms and for me it came on rather quickly and unexpectedly. So you might want to check that you (or miscellaneous objects) have not unintentionally engaged that “B” mode. (PS: it does show up as a highlight on the “B” on the MFD, but I just never noticed that subtle change in highlighted transmission mode until after a Priuschat member had figured out what my problem was.) Good luck!
Thanks @FuelMiser Actually just as a quick update; no word back from my mechanic. Fortunately we have an extra car; so I'm not in a rush to get the prius back. The cat coming loose sounds like a very real possibility; as I've had a bunch of rattling coming from the bottom of the car. I thought it was a heat shield however it very well could be the cat. What does "ICE" stand for?
Afternoon all - Got my car back Mechanic ended up checking the cats which were ok; however the 12v was the problem. I ended up doing ignition coils, tranny fluid; and spark plugs since I was there. Car runs like a camp. Thanks @FuelMiser @Greenteapri @Robert Holt @Mendel Leisk @scona @Raytheeagle for your insight on this one Happy holidays!
So seems like I was too quick to claim victory on this one. I think I still need to do the cat. Which is where the rattling is coming from