Saturday, July 28, 2007

The Prius doesn't have torque in reverse?

On my way to the basketball court today, a man pointed at a car parked on one of the hills near my place and asked "Do you know whose car this is?" 

I said I didn't.  Then he proceeded to tell me that he was asking because he was hoping someone could move it.  It turned out that his Prius was parked behind the car and he did not have enough torque in reverse to back up the hill.  The Prius drifted forward even while giving it full throttle in reverse.  I proposed that we get a couple more guys and push the car on the frame around the doors while he jammed on the gas.  At that point I think he had potential liability lawsuits flash through his head and decided to call AAA instead and get them to winch or tow the car.

I found this really surprising about the Prius.  Granted, we live between the fourth and seventh  steepest streets in the city, and he was on the 27.9% grade part of that hill trying to back up.  Still, my four-banger Subaru has no problem backing up that same stretch of hill and it supposedly has less torque than the electric motor in the Prius.  I also thought those CVTs in the Priuses were essentially supposed to deliver the same power in reverse.

I found something on the net that said this was an older Prius problem, but his was a pretty new looking Prius.  At least a 2003.  Maybe in this case his batteries were low and the gas motor doesn't have enough muscle?  Or is this just a known issue?

1 comment:

Anonymous said...

The Prius CVT is unable to reverse the direction of the gas engine torque, and thus the only available power in reverse are the electric motors. On the older Prius, the main electric motor only has 35HP and there were indeed reports of problems backing up in San Francisco. The second generation has a 50HP electric motor and fares a bit better. It is amusing, in any case.