I am using a 2012 Prius and I was running around 23KMpL average. For sometime I am seeing my mileage around 17 - 18 KMpL. What could be the reasons for this ? The only change happened in between is that I had a accident which I had to replace the front buffer.
If it remains consistent, I'd suspect some kind of mechanical damage creating drag which eats up fuel. A dragging brake pad perhaps? Maybe someone didn't finish the repair right and power is bleeding out forcing the ICE to kick in more to recover power for the battery. A simple frayed wire on standard ICE vehicles have been the cause of many a problem with dying batteries or equipment failures, so why not the same for a Prius?
I refilled 3 times and all 3 times the mileage was well below 20. However, after the accident I waited for a month and a half since the dealer did not have the font buffer available, there was no issues with the mileage during that period.
Was it a Toyota shop or independent shop? With Toyota, they could "investigate" and repair their cock up under the guise of it being a warranty issue. An independent shop would be more problematic.
Local Toyota dealer working under Toyota Corp. However, this is beyond warranty. I am not sure whether they have anything for repairs.
Tyre pressure is fine. Analysis on the 12V battery came positive and the battery is only 2 years 8 months old. Today I handed the vehicle back to Toyota for an inspection. I explained them the exact scenario saying the I noticed the drop after getting the vehicle back from the repair+regular maintenance service.
Well, it's clear it's involving the mechanic/shop. Get someone higher up in Toyota involved if the shop won't figure out what they did wrong at THEIR expense.
I did that. They had an inspection and said there's nothing wrong. However, they said that have done a reset in the hybrid system. They want me to run for sometime and get back to them on this.
Are you interested in learning how to investigate and diagnose the problem IF it returns? It will require some instrumentation, a miniVCI with a laptop running Windows XP would be the starting point. This can give real data to try and understand what is going on. What does this car typically do each day (i.e., taxi, delivery service, commuting)? Bob Wilson
Bob, I would love to do that. I work 38 KMs away from home and this is my commute everyday. My daily average was about 24KMpL using highway. Through the normal road, it's 26 - 27 KMpL. I never went pass the 20KMpL mark after the repair/service. However, after the reset, first the first time today I managed to get a 25KMpL on my trip to work. This is strange.
I'm not sure what they do in the recall, but software can load buggy. When in doubt, reboot? I doubt the Prius software truly "shuts down" when you turn the car off, and a "hard restart" is done by a mechanic.
They told me that they did a hard reset. Do not know what this means when it comes to cars. All I know is my phone performs better whenever I do a hard reset.
"reset" - disconnect the ground wire for 2-3 minutes to let the caps discharge By doing a power-on reset, the stored engine and vehicle metrics are cleared and any changed metrics like the 'backup beep' are cleared to their default state. It takes the car a few trips to relearn the fuel trim metrics and then things return to normal. Let me suggest a warm-up effect test for the first trip of the day: put car in "READY" and hit "EV" to inhibit starting the engine clear a trip meter turn off "EV" and let engine run until it auto-stops, ~60-80 seconds drive normally to work record trip meter data . . . do this 3-5 times What this does is warm-up the catalytic converter and coolant enough to put the engine and car in the most fuel-efficient mode while burning the least amount of fuel. Then during the rest of the trip, the car will burn the least amount of gas. Now there is an advanced technique but a little tricky. Start the car, fasten seatbelt and adjust radio and mirrors. Then for the first minute, shift the car into "N" to take all load off the engine when you can and take the lowest speed route possible. But this technique takes practice and may be too distracting. GOOD LUCK! Bob Wilson
Thanks Bob. Let me try this and see how it works. Really appreciate these kind of tips ...! Overall I feel that the reset has done the trick as I can see the running average is coming back to my normal figures.
Getting back to everyone what I observe after a week. It seems like the hard reset has done the trick. During the last week average mileage for my office drive and return came to about 24KMpL. However my running average is still around 20-21 KMpL due to the short trips that I make over the weekend. Once, I went up to 26.2 KMpL and this was something I have never seen for couple of months.. I am concerned of something that the local dealer told me. They said that the system can behave like this time to time and hard reset is the solution. Can anyone in the community confirm this, specially in locations other than Sri Lanka ?
I am almost at sea level. It's hot and humid in Sri Lanka. Average temperature is around 28 - 32 c. (80-90F)
