Falling Gas Mileage on '07 Yaris - Toyota Nation Forum : Toyota Car and Truck Forums

Accessdabbler · 11-21-2008, 01:51 PM

Just bought a 2007 Yaris sedan a couple months ago (former rental car with ~43,000 kms on it). The gas mileage then was about 5.7 L/100 km (sorry, not sure what that is in MPG) which was great! However, it suddenly now is getting 6.4 and, most recently, 6.7 L/100 km.

I discovered a LARGE amount of leaves in the tank below the air filter (an animal may have been building a nest in there) and cleaned it out but the mileage is still getting worse. I didn't replace the filter but I did vacuum it out. Considering replacing it, though.

What else should I be looking at to see why the mileage is getting worse? The car has about ~55,000 kms on it. Oil was changed recently. Tires are OK (just put on snow tires).

MrSo0h0o · 11-21-2008, 02:11 PM

It may just be the weather changing. Colder weather requires more gas to start up and warm up.

Accessdabbler · 11-21-2008, 02:20 PM

Possibly, but that's a 20% difference since June...

craigq · 11-21-2008, 05:19 PM

Yup, with the colder weather the mileage will drop, summer average is about 6.2-6.3 L/100KM, right now our Yaris' average is closer to 6.7-6.8 L/100KM. It'll likely drop to 7L/100KM in the coldest months...

***CDNVITZ*** · 11-22-2008, 06:56 AM

I have the same situation.. It's just the weather.

-Rick

thebarber · 11-23-2008, 11:14 PM

cold weather = denser air = thick, cold oil = engine warm up = using defrost = worse mileage

i get 6.6L/100km in summer, all city and 7.5-8L/100km in the winter, all city

im surprised you never noticed this phenomina in any other car youve owned...

Nigal · 11-25-2008, 06:38 AM

Something else I have noticed is that when I'm nearing my 5,000 oil change mark of I have gone over the mileage goes south. Same with the air filter.

***HATEnFATE*** · 11-25-2008, 07:41 AM

Most people don't realize that the winter blend of gasoline will also reduce your fuel economy. Diesel isn't the only fuel that changes blend in the winter.

Accessdabbler · 11-25-2008, 07:22 PM

Hmm, well my latest fillup was half a tank and I got 7.2 L/100km this time. It seems to get worse with each fillup and it's not even really cold yet! At what point do I take it in to have the mechanic check it out? My '96 Protege had 7.8L/100km lately so I'm a bit concerned something funny is going on...

yi5hedr3 · 12-08-2008, 04:47 PM

Ethanol will knock it down....lower air pressure in tires......cold weather in general. Yep, winter is bad for gas mileage!!