Severe Mileage Drop

Cold weather is the major issue. Your other factors appear to be fine. You don't really say how low your temps are, but generally, cold weather will affect the rigidity of the bladder in the fuel tank, and decrease the amount of fuel that can be pumped into the tank. Do not try to judge mileage (or loss of mileage) by when the first pip disappears on the fuel gauge. If your "normal" mileage is 48mpg and now you're seeing 46mpg, that is not a severe mileage drop, and can be accounted for by the colder temps. The cold will also cause more green bars to be displayed.

I'm not sure what the chirping parking brake is, but if the parking brake is misadjusted, it can reduce mileage as well.

 

If you want real help on an issue like this, fill out your profile so that we know where you drive, how long you have owned it, and information like that.

What you describe sounds like normal winter operation: drop in mileage, more green bars, and reduced fuel tank capacity. This is all normal for a Gen II Prius.

Tom

 

hey.........dont feel bad. I'm in the same situation and it's all weather related. Cold weather is really tabooooo with the prius and everyone is in the same boat.

i can't get 100+ consistently, but on occasions, yes. now, i'm from 60-80 before the first pip goes away. if i'm not careful, i'm 170-180 as the FIFTH pip disappears. just practice a lot of P&G and drive frugally. I'm over that under certain situations and the mileage really drops!

The way i look at it is when i want to, i can see awesome mileage once again.

 

So i tried this technique and found that my battery after 1 year is as follows:
Unload: 12.4V
Load: 12.1-12.2V
Charge/Start: 14.2 V

I don't think my decrease in mpg is due to the battery or weather. Today I got 38mpg after 75miles going 80mph from SD to OC. I used to get a consisten 45-46mpg no matter how i drive. I really don't know what the problem is and I need to find out because the only reason i bought the car was for the mpg since my commute is 180 miles/day. So i may have the same problem as you, can anyone help?

 

You were formerly able to get 45 MPG at 80 MPH? That's almost unreasonably good.

Has it been a lot windier recently? More MPGs are lost in a headwind than can be gained from a tailwind, especially at those speeds.

Even if you never get the fuel economy back up consider this: what other vehicle would give you 38 MPG at 80 MPH?

 

Check your tire pressures. COLD should probably be around 42F/40R. The coastal storms were blowing in from the west & northwest. If you were driving from SD to OC during any of the blustery weather, you'd be driving into headwinds.

For what it's worth, I made the drive from SD to LA and back everyday - 125 miles one way. Driving at 80+ MPH gets old after awhile. Too much tension dodging around slow pokes. Get into the zen of the Prius and and save yourself gas money and lots of worthless stress, and join the crowd in the slow lanes.

It might be a challenge at first, but soon you'll be enjoying the scenery, chillin' to some tunes, and actually relaxing on that big drive. Then you'll be racking up MPG's in the 50's.

 

You seem to be doing everything fine, no worries.

Heyy, I live in Buffalo & it's been way below freezing here and I'm almost scraping into the 30's as far as MPG. My car wants it to be spring soo bad!

 

Hey Tom, what MPG do YOU get with your '06 in those presumably frigid N Michigan winters? I'm in N Ohio and my '06 gets mid-to-low 30's driving around town, the only reason i can stretch into the 40's right now is because of my hwy commute.

what year is your prius? By scraping into the 30's does that mean low 30's or high 30's? I'm in a similar climate in Cleveland.

 

Uhh.. About your oil level: how high is a little high?

Anything over the top line is overfilled and CAN reduce mileage.

 

One thing I have read, that may apply, is that the cold weather makes the gas bladder less flexible. Since I am a new florida owner, I cannot vouch for this, but it might be applicable to you.

 

I hate when people complain about this stuff. I often fail to get 30 miles in winter before losing a bar. And 30 is not out of the question in winter. Seriously, you get 48 mpg and complain????????????? ridiculous.

 

I've recently noticed a mpg drop in my 2006 Prius. I used to get 40-45 mpg now I'm only getting around 35 mpg. My driving habits haven't changed and I don't think it's the cold. I just had my oil done and my tire pressure is good.

Any ideas?

Thanks

 

Check that they didn't overfill your oil.

 

For almost a year my 2009 Prius got great gas mileage. Without even trying, I easily averaged 45-47 mpg per tank of gas, occasionally even higher. But in late December my gas mileage began going down significantly. It has gone down about 20%. Even with trying ‘hypermile’ techniques, I have a difficult time even getting 36 mpg now. About 6 weeks ago the ‘check engine’ light came on and stayed on for 2 days and then went off. In addition, the car often ‘shudders and shakes’ when I come to a stop. There have been no changes in driving habits or amounts of driving. Yes, we've had some cold weather, but I had no mileage problems last winter. I took it in to the dealer a couple of weeks ago, but after waiting for 4 hours they were unable to diagnose the problem and said to come back when I could leave it longer. Very frustrated.

 

"Oh, so you know what I'm talking about LOL You mean 170/180 when u just go below half a tank?? wow... More reason to keep up on the tire press, air filters, good fuel, ..... car washes...... waxes "

TX TABBY - 42/40 - new air filter on every other oil change - OIL BY SHELL - car washes by none other, wax by meguiars, tech wax