I went through the same thing a while back... During the summer I drove quite a bit, probably about 50/50 city and highway and I was averaging about 20 MPG. I was getting about 300-330 miles per tank. Now I make much shorter trips, it's colder, and we have winter blend gas, and I'm getting around 15 MPG or around 240 miles per tank.

IMO, I think taking the shorter trips has had the largest effect on my mileage, cuz I started noticing a difference way before it started getting cold.

 

Sorry, I don't know.


The nose works better than the eyes at noticing fuel leaks. But us goats have big noses.

 

THe other thing to consider is that a clogged Catalytic converter can killer your mileage. I don't know how prevalent that is in Yotas though. GM trucks have lots of problems with this.

 

Man I get better gas mileage than that and I've got 35's and a roof rack

Something very wrong there. O2 sensor?

 

Has it been 10,000 miles or more since your last air filter change?

 

nope not yet, filter is still pretty new

 

im going to fill up tomorrow and ill post up what mileage im getting. right now im at 120 miles and the needle is on the 1/4 (first line) mark. im feeling depressed.

im hoping its something simple like the o2 sensor, but thats 100 bones out the window if im wrong.

 

Any chance someone is stealing your gas?

 

nah, i wouldnt blame them tho the way prices are going

 

I'm having an issue with my mileage too and it's off by about 50 miles a tank and a couple of months ago my I had a CEL indicating TPS problem and I cleared the light and it's never come back on but I think I could still have a problem with it anyway but my mechanic did a full check on it and all the readings were correct and checked my other sensors and didn't find a problem.

I'm at a loss since I don't want to just replace things and still have bad MPGs.

 

just a thought, ive been warming up my truck for about 10-15 mins each morning. Could that be sucking down a significant amount of gas??

 

Yep, you get 0 mpg sitting still.

 

ha that is true. Does it really suck down that much more gas when its cold out just sitting there with the heat on tho? id find that hard to beleieve

 

It does suck down a significant amount of gas when warming up... Mine can idle at up to 1500 RPM when I first start it up, but when it finally warms up it idles around 600. Basically I just have faced the fact that in the winter I'll see my MPG dive.

 

You don't need to warm up the car for 10 or 15 minutes. In really cold weather, like less than 10 degrees F, it's reasonable to give the engine no more than a minute before driving. Otherwise, 15 seconds is fine for getting oil flowing.

When an engine is cold, the fuel mixture is enriched with more gas. As the engine warms up, less fuel is brought in relative to the amount of air. When the engine is idling, it really has a hard time warming up. So you spend a lot of time in the warm-up mode. Driving helps the engine warm up faster.

You should still take it easy when it's cold. Your tranmission fluid and differential fluids are cold, too. I've heard it takes about 10 minutes after your coolant has reached operating temperature before your engine oil is at full temperature.

Cut out the 10 to 15 minute warm up and I bet you'll see a big jump in gas mileage.

MadCityRich

 

i disagree. i think it takes more than just a minute if your truck has been sitting out all night in the cold before you drive it. if you let your truck oil get to a good operating temp, your oil will lubricate the enigne and you will be a happy camper.

after all theres a guage for oil temp. :]

 

im just a wuss and i like the truck to be toasty warm when i get inside. Im going to try to just let it warm for 5 mins from now on and see if that helps.

 

It's probably a gauge for oil pressure, not temperature. Some Toyotas just have an idiot light for oil pressure.

Oil lubricates at any temperature. The question is how well it flows. Cold oil is more viscous, meaning it's more resistive to flow. But if you use the right oil grade, there is no problem with lubrication. That's why you don't want to go with WOT with a cold engine. But normal driving is just fine.

A minute is plenty of warm up time.

MadCityRich

 

ok filled up tonight. 11.13 gallons with 129 on the trip odo, for a whopping.....drumroll............11.59 mpg!!!

something is definately wrong, even with winter gas and healthy 15 min morning warmups.

 

i just ordered a new front o2 sensor for URD. Hopefully that will be the fix, its probably the first thing to cut my mileage in half.