Significant reduction in MPG between 2004 and 2005 Prius'

some have reported that a "broken in" Prius seems to get better gas mileage. the difference in total mileage on the car may be the reason.

as for the filler tube. you should not try to overfill your tank. the gas pump you are using has a sensor that triggers the fuel shutoff switch. that is why you cant seem to get the pump to run after the fuel is shut off. it takes about 30-45 sec for the gas to completely drain back down again.

next time you have this problem, try this. after the pump shuts off the first time. remove the filler nozzle. let it sit a minute or two then pump again. when it shuts off the second time (assuming you can get a few more gallons in) hold the nozzle tight against the filler tube to catch anything that might bubble out.

a small amount of spilt gas reeks havoc on the environment.

 

the bladder tube problem was fixed (so its been rumored) about half way through the 2004 model year. so all the 2005's have the fix (well as fixed as its gonna get)

on the nozzle. if you look at it, it has a small hole next to the big hole. that is the backflow sensor. when it senses backflow, it shuts off the switch. it takes as much as a minute to reset itself. without resetting, the pump will not run to fill even an empty tank.

i have experienced the same thing and have noticed that some pumps dont seem to reset at all no matter how long you wait. i feel that the reset is tied to the pump switch (the handle you flip when getting ready to fuel)

but dont really know. but at the same time, i dont have that much of an urge to stretch my tank. i usually fill up within 20 miles of the blinking bar (if i wait that long. have actually only seen the blinking bar about 3-4 times)

UPDATE...

looking at my mileage chart, i can say that ive seen the blinking bar probably 4 times since i have 4 fillups between 9.6 and 9.8 gallons.

i frequently take trips of over 100 miles roundtrip so i try not to do those with less than 2 bars if possible. i rather get gas at the station i am familiar with if possible.

 

I agree that it's simply a matter of getting the car broken in. Our 01 is out performing the new 05. However, on Friday we topped the 1000 mark and I noticed a significant difference in the car. Almost like 1000 was a hard set number in code somewhere and things changed when that number was reached. I don't really think this, but wouldn't be surprised if that was the case.

 

Re: Significant reduction in MPG between 2004 and 2005 Prius

I have noticed no change whatsoever in mpgs since my car was new, and it now has almost 15,000 miles.

 

Re: Significant reduction in MPG between 2004 and 2005 Prius

In July, I noticed a big dip in MPG just by getting new tires. That alone made a difference.

I also noticed the engine shut off didn't smoothen off until around 7,500 miles.

We all know that oil-level & tire-pressure make a big difference too.

And with my Classic Prius, I observed MPG improvement due to break-in all the way up to 30,000 miles.

Lastly, when was the last time you filled up? Is a possibility that the 2004 is still using summer-formula gas and the 2005 winter-forumla gas? Could one simply have different gas, like one being an ethanol blend and/or a different brand.

So you've got several factors at play to look closer at.

 

Re: Significant reduction in MPG between 2004 and 2005 Prius

That could be the result of timing... MPG improvement cancelling out the reducing affect of winter-formula gas and lower temperatures.

 

Re: Significant reduction in MPG between 2004 and 2005 Prius

:?

I have had my 2004 Prius since April. Intially I averaged about 49 miles per gallon. In August I got the 5000 miles service done and it immediately dropped to about 43 mpg. We went on a vacation and I thought it was due to the different conditions but it stayed lower all fall. Well a few weeks ago I got the 10,000 miles servicing done and now I am averaging about 39 mpg. We just checked the tires and found the right front one to be about 4 pounds too high but the rest of the tires were on target with Toyota specs. I have never over inflated the tires in an effort to increase mpg. Do you think the right front tire being over inflated could have impacted my mileage this much? Any other ideas?
Tara

 

Similar experience here. I was averaging 49mpg pre-5k-mile oil change, and 45-46 after. I just had the 10k change, but all bets are off regarding oil as a factor. Today, I noticed that the dealer sticker said they used 10W30 oil, even though the Prius manual specifies 5W. I called the dealer and complained, and the asst svc mgr said "We put 10W30 in all Toyotas, because it's most appropriate to the southern CA climate."

Further dealer service beefs: At the 5k service, they OVERFILLED the oil and UNDERFILLED the tires. No idea what weight oil they used, because that line on the sticker was blank.

When I made the 10k service appointment, I asked about the 40L brake light switch TSB, and they said they had the parts in stock, and they'd do it too. After I brought the car in, they said they'd have to order the part after all, and that I'd have to bring the car back again.

To add insult to injury, a tire exploded on my drive home from work today, 24 hrs after the service. Coincidence, or (dramatically) wrong tire pressure again? Either way, Toyota Customer Service is about to get a scorching letter from me. :cussing:


At least a package from Coastal with my XM, EV, and door lock mods will be arriving tomorrow.

 

Re: Significant reduction in MPG between 2004 and 2005 Prius

<div class='quotetop'>QUOTE(tara\";p=\"60394)</div>

I wonder if they used the correct weight of oil.

 

Re: Significant reduction in MPG between 2004 and 2005 Prius

I think that all prii should use Mobil-1 Synthetic Oil. Its the best oil out there. I have to use it in my Evo. Plus, its a synthetic oil (for you treehuggers). :mrgreen:
<--[Evo]

 

I have a 2005 w/ almost 260,000 miles. I am just starting to see the bladder issue after owning a month. When I first bought it the tank was full up. It took like two weeks to get to 3 clicks from empty. I have had Jaguar that used premium 91 octane or higher only. It got like 16-18mpg. The tank was about 11 gallons. I figure I am getting 46-48mpg now. I can handle 5-6 gallons. I am still driving like 300 miles between refills, lol. Thats better than 250-300 at Premium prices.