well here in southern california its warming up fast and getting to the 90's and soon the triple digits. lately it seems like my gas mileage has dropped and im thinking maybe the warmer weather has something to do with it any ideas?

 

makes sense... colder denser air produces better power results....

 

At those temps you are probably using your AC, right? Contrary to what some people say around here, that compressor doesn't run free. The engine spins it, and you pay the price. How much really depends on how you drive and how cool you like it.

 

hmm, i got worse mileage in winter... 11mpg, vs the 14mpg im getting now...

 

no i dotn have ac or power steering so thats not affecting it. is there any way to counter act the warm weather?

 

Never checked the milage difference from hot to cool or cold weather. I do know that my Tacoma loves the temp below 60 degrees for some reason. It runs like a scared rabbit in the cooler temps.
Maybe the hot or cold air acts different on the air sensor or the air just flows easier when it's cool.
I'm just guessing here but I'll bet the hummidity or moister in the air from one reagion to another would make a difference also.

 

Yes, there are a ton of factors that come into play here. Barometric pressure, ambient temps, humidity, oil weight, "summer" vs "winter" fuel, vehicle condition, etc...

Track your mileage and give us some figures...right now we have no idea what kind of difference you are talking about.

 

its about a 4-5 mpg a diffrence, its a pretty good amount.

 

could just be a co-incidence... had that happen numerous times with my yota, thinking the problem MUST be related to one thing or another, but just by fluke something decided to die at the same time. could be a faulty o2 sensor, or one of 100 other things.

 

I've tracked my mileage from day one for both 4Runners I've owned, even plotted the monthly average (pretty anal, huh?). 15 years of data show a significant drop in the winter, but then again, I'm in the north. The plot almost looks like a sine wave. I typically lose about 2 mpg in winter compared to summer. Also, I rarely use my A/C.

 

Same here. Warmer, less dense air = less power = less fuel needs = ECU and sensors doing their job.

 

I've actually been getting better fuel economy as it has gotten warmer here, and I do run my A/C pretty much all the time. It is true that the A/C uses gas, but if you drive around with your windows down the increased wind resistance will eat up all the gas you save, and probably more. As stated above, too many variables...

Anyhoo, if your mileage has dropped by 4-5mpg something is screwy. O2 sensor maybe? Clogged cat? Could be a lot of things.

 

O2 sensors are new, and vac. lines are new too. ive pretty much gone over my whole engine since i bought it back in september because i wanted to make sure it wasnt going to break down on me while i was on the trails some 50 miles away from home

 

Mabe this is due to driving in 4wd? My milage seems about the same year round unless I am using 4wd in the snow. Then it drops like a rock due to the resistance and slow speeds.

 

I dont have 4wd so that isnt a factor for me

 

Sounds exactly like mine... and now I can have the tailgate window down!!! - Man, I've been waiting a long time to do that...

 

i noticed my carbed ford 351w ran smoother and had better gas mileage in the winter. havent noticed a difference on my 95 pu.


time to get some guiness

 

im believing it might be my tps sensor. i know it is adjusted right but for some reason i get a drop in engine rpm every now and then and it is only when it is warm or hot out, something might be related. im not going to worry about it too much though, the 3.4L is going in later this summer

 

Does Canada suffer from the "winter gas" issues that the US does? My mileage dropped 3mpg from October to about 2 weeks ago. I'm pretty sure it's the whole winter gas thing...