ive noticed when temps fell below 27 degrees my prius does something odd. After starting the car I drive off right away after a few seconds of idle time. I can drive a block or two and come to a stop sign, engine still running but when I go to accelerate it starts off ok but it then feels like a loss of power almost like a slow start on EV only. 2-3 seconds later the engine changes rpm and power returns to normal. No lights, no errors and @ 76k miles
Well when the engine is cold, it'll run on battery power (even though the engine is running). It'll rev up when the engine is at a minimum temperature or you force it to rev up (accelerate hard, not recommended unless you had to get out of the way of a hazard).
Yesterday it was 34 and today it was 41 and did not do it. But anytime below 30 degrees out it does it. I have ran chevron through it and sadly that caused my mpg to dramatically drop. I went from 52mpg and currently at temps around 19-29 im averaging 34.9-35.4. The 12v battery is the original and idk if it is getting weak. I had it tested and the toyota dealership said it was fine. The only other odd thing I noticed is the footwell lights used to go off when the car was put in drive. Now they don't. They dim slightly but do not turn off and when it is put in park they brighten again. Idk if the two are related in anyway but it just seems kind of odd
This sounds like things well within the warm-up period, before the ICE starts generating power. Is your grill blocked?
Yeah she might be a cold blooded bitch. This is the first winter with this car. Time to learn her quirks I guess. This is the first gen III i have owned my gen II's didn't do this lol
The intake manifold gets clogged up over time (100K) and causes a progressive loss of power. That could be the problem. If it keeps getting worse and chugs a little going up hills thats your problem. There's a thread on the forum of how to fix it. Took me about an hour to take it off and clean it with pipe cleaners and degreaser. I believe its a faulty design on some of the earlier Gen III intake manifolds. Mine was bought in aug 2009.
Nonsense ..... !!! As others explained this is the "expected" behavior when ICE is not up to operating temp.... For OP if you have temp monitoring like scangauge... watch for cooler temp... around 71-74F in idle you can hear a distinct change of engine noise that is when ICE will power the car (unless described as emergency) until then it "tries" to go on EV if enough charge or 'reduced' power .... I got this reading PC posts there is a thread on warm up vs mpg loss or something like that with. I believe BobWilson did some measurements on this and had detailed analysis what is going on and had some recommendations based on his findings... And as OP said it is repeatable ...
It's normal for the system to take advantage of the battery-pack when the engine is cold. Living in Minnesota, I experienced that on a regular basis with all 3 generations of Prius I've owned... the Classic, the Iconic, and the 2010... especially due to living at the bottom of a large hill and needing to do the climb right away. It was no big deal, since there's no concern whatsoever about the battery-pack being stressed. NiMH works quite well when cold.
