Used to get 650KM now getting 500KM per tank

[chattersking]

Hello Everyone,
I would appreciate some input into this situation. I have a 2008 Yaris Sedan, in optimum condition treated like a baby and always using Shell and cleaning fuel injectors every 15000KMS with Seafoam. Tire are always properly inflated and driving is mix of highway and city from Delta to Burnaby BC about 48 kilometres round trip to and from work.
I used to get 650+ Kilometres per tank before, however lately its around 500 or even 440 and this has been an ongoing problem well through Summer.

Any thoughts?

[WeeYari]

Congratulations. You are now getting what I have always gotten.

[firemachine69]

Slow down.


And stop using Sea Foam! That shit destroys rubber seals!!!

[digitalrain]

I also lost my awesome MPG on the old Echo I had. A few things for me were.

Underinflated tires, worn spark plugs, and rotors that were dragging a bit due to moisture in the brake fluid(the pistons? weren't retreating properly). Also just due to higher mileage on the engine.

You're getting phenomenal MPGs by the way. Wish I was getting even close to that in the city. I get about 420 klicks per tank in the city (36 MPG)

Originally Posted by chattersking

Hello Everyone,
I would appreciate some input into this situation. I have a 2008 Yaris Sedan, in optimum condition treated like a baby and always using Shell and cleaning fuel injectors every 15000KMS with Seafoam. Tire are always properly inflated and driving is mix of highway and city from Delta to Burnaby BC about 48 kilometres round trip to and from work.
I used to get 650+ Kilometres per tank before, however lately its around 500 or even 440 and this has been an ongoing problem well through Summer.

Any thoughts?

[Ilovemyyaris]

When is the last time you changed the oil?

Also I would do more research about this Sea Foam stuff.

[Nanook]

O2 sensor?

[MadMax]

Winter gas, or do you have that year-round up in Canada?!?

[Picklemitts]

I get 27mpg in my Yaris, and about half of those miles are highway.

[caineroad]

will EFI cleaning help? or fuel injector something like that?

[caper26]

Originally Posted by chattersking

Hello Everyone,
I would appreciate some input into this situation. I have a 2008 Yaris Sedan, in optimum condition treated like a baby and always using Shell and cleaning fuel injectors every 15000KMS with Seafoam. Tire are always properly inflated and driving is mix of highway and city from Delta to Burnaby BC about 48 kilometres round trip to and from work.
I used to get 650+ Kilometres per tank before, however lately its around 500 or even 440 and this has been an ongoing problem well through Summer.

Any thoughts?

The reason I just visited this forum was for the SAME reason. My car was new in Apr, and since the fall arrived my mileage is about the same as yours... I was getting 650+ km/tank (5.5 L/100km ish), and now can't come close to it. Last 2 tanks were 7.0 and 7.2 L/100km. Yuk. Only 10,000 km on car. I do live in Nova Scotia. Not sure if you can see this link, but there are graphs of my fuel ups. [LINK]

[digitalrain]

To OP,

Did you ever find out what was going on with your MPGs?

[jambo101]

I noticed a big drop in mpg when i changed the original tires on my 08 sedan.maybe a 15% difference, also i think the gas companies change their gas formulas for winter that also adds to a decrease in mpg

[wildcard]

running the heat in defroster mode alot ?

[Betrivent]

Perhaps the MAF sensor needs cleaning?

[thebarber]

Notice a lack of power or anything like that? Maybe a piece of the catalyst has broken and is clogging the exhaust route?

[caper26]

any update yet? I had same problem and seemed to have fixed it ... peprhaps.

[blue_rider]

Recently, I've also noticed a drop in fuel economy for my 2007 Yaris liftback (67,900 km).
I was happy with getting between 600-640 km/per tank (city/hwy combined), but recently have found it to be roughly between 500 and 540 km/per tank. I found that I got approximately 80 km per "bar" when things were right but need to fill up sooner than before for some reason.
Toyota did a throttle body clean and fuel injector service not long ago (63,000 km?)

I've just replaced the original Potenzas (almost no tread) with new Michelin "Defender" tires, so I'll see if gas mileage improves a little with those, plus I am due for oil and filter change next week.

[caper26]

did you read my thread similar to this one? I cleaned the MAF sensor, vacuumed airbox and air filter, used some lucas fuel treatment and changed gas brand....as well as summer tires back on.