today, i started my vehicle after a 4 hour rest, 2005 Prius. when i started the battery fan come on at a moderate speed, then i took off to drive, driving through the parking lot i noticed it drove normal, then when i went to main road, its as if i lost half of my total horsepower, the power was down to barely nothing, i was flooring it to get up to the speed limit of 45 mph, my battery was all green, completely. As i finally got up to speed, the battery fan shut off, i set cruise control to 48 mph and watched my MPG gauge, going on a fairly slight upwards grade the vehicle was getting about 80 to 100 mpg, as i went for another 3 miles the car was very slow. After this the vehicle ran normally. Anyone have an idea why this happened? It was really weird because the battery was completely full in the parking lot and the engine was continuously charging it, even when i was stopped.
My first thought is, "hot battery." How hot is your OAT today, and was the car parked in the sun? I've had an episode of sluggish performance on an extremely hot day with a battery that was hotter than usual (105F). As the linked post describes, the ICE cut on in circumstances where it always cut off previously (and since).
I would think it's a mix of hot battery and the car trying to be nice to it during it's "warm up cycle".. which should have only been a block or two. Normally the car takes power from the ICE and the electric system does most of the work till it "warms up"... well.. if it's only sitting for 4 hours with a full battery.. it may have been too warm.. so to keep temps from going up, it prevented heavy electric use. or it's just simply hot. since it's been 104 here lately, i cruise and don't expect certain power bands from time to time... i also run my a/c/ around 85 degrees though...
