20MPG to 13...WTF?

I've been driving Tacoma's for quite a few years now and every winter my mileage takes a hit,but not like this. Usually drop to the mid 16's this year the last 4 or 5 fill ups been the high 12's to 13.5. 2013 DCSB V6 with 25000 on it. Same fuel same type of driving. Anyone else? Anything I'm missing that I could look for?

 

Driving habits? Another driver with a "lead foot"? Catalytic converter, doubtful with only 25,000 on it. Unless you've been burning CRAP gas.

 

Pretty much routine stuff up till this point. Tire rotations every 5 and oil every 4000 miles done by myself. Only thing that may feel different is the tranny, seems to always be searching for the right gear lately.

 

Did you try a different brand of gas? Winter Gas Mixes may affect the mileage. Trying a different brand my show a difference ??

 

More ethanol in the gas?

 

disconnect the negative terminal for 15 minutes..........trans should shift firmer and more consistent

 

Thanks, I've done this in the past so I could let the truck try to "learn" a new set of shift points, but I'll give it another shot. Yea winter gas here in the Northeast sucks and does some weird stuff but stations I deal with don't bump Ethanol above 10%

 

Any O2 or fuel sensors to check out?

 

My 2011 Access cab with 62000 miles just did the same. Always ran a solid 20 mpg, went to 16 within 2 weeks. Thought I had a fuel leak. Truck was running fine.
Changed the plugs and ran some Techron thru it. Back up to 19mpg.
Personally I think they are adding more ethanol this year but that is strictly opinion based.

 

Last tank in mine was 15, down from 19.

 

GREAT Screen name. You should copyright it before Toyota changes the name of the Tacoma to "DILLIGAF"

 

Time for spark plugs, air filter and switch the rear diff oil to synthetic.

 

Mine did that but it might be because of supercharger and bigger tires.

It gets cold outside, it'll typically run richer. Do you let it idle a lot more? Anything like that?

 

Are you letting the truck idle for a long time to warm up?

Remote start or letting it run for a while before driving will burn more gas.

 

Plugs at 25,xxx??

 

I would.

 

They're due at 30k.

 

Funny. My mileage has dropped significantly in the past month or as well. It typically drops a few MPGs when it gets cold, but this year has been worse than usual. I'd imagine its this year's winter blend gas.

 

I originally thought the same thing about this years winter gas,especially since it's so much cheaper this year...lower prices less profit for big oil..lower quality so MPG's drop,drivers need more gallons to go the same distance..profits back up! But that's just my cynical conspiracy theory.haha. But that's also why I posted the question. If that was the case, we'd all be getting shitty mileage. If it's only a few of us there must be another smaller cause. Thanks guys, guess I'll start with a different gas,then try plugs.

 

Are you getting the same results tank-to-tank? Perhaps you got a bad tank of gas..... or the ethanol is actually higher than they're advertising. You just don't know.

I haven't been monitoring mine like I normally do...but my scangauge has been pretty accurate, so I'm assuming my gas mileage has been consistent.

Have you checked your tire pressure lately (when cold) ?