I'm just not frugal in daily driving to and from work or running to the store or whatever. But I try to do well on road trips and such.

 

Misread trrocks post, you may have misread mine ... your "look at the receipt" = my "gas pumped", your "how many miles were driven" = my "trip odometer reading", unless you're suggesting that you can accurately calculate mpg's without filling to pump shut-off then we're saying the same thing here ...

But yes sorry trrocks, should have read your first post more carefully, . You bring up a good point and have presented good data. As far as mpg tips all I can add is one I read in Consumer Reports, combine short trips ... engines are very inefficient when started cold.

here's the link

 

Yea, same thing, I thought you were trying to calculate strictly off the needle.

If you really want to improve it, turn the car off at stop lights. It's a proven fact that cars now use substantially less fuel to start than to idle.

 

i get about 27, and i do top off...

but i drive it like i stole it, and still get good MPG..

highest was 33, lowest was 23..

not much more here to say on gas saving tips unless you get into improving engine efficiency with exhaust, etc.

 

haha I'm getting the feeling I've Lost a bit of efficiency with my exhuast and intake considering the mileage I'm getting and the way I drive (fairly conservatively). I've been pretty good I thought, and my BEST results get me 23.5 mpg tops (only ~20% hwy). Does this seem normal or should I talk to my dealership?

 

im getting on average about 23mpg.. i think alot of the reason is that my car doesnt warm up untill im a mile from work. I do alot of really short trips and no highway driving at all

I guess in a sence i use less gas per day so i cant complain that my milage isnt higher

 

The best solution IMO would be - if it were possible with this car - an ECU reflash, which is an option for Hondas, Nissans, and others, but not Scion. You could tune for either maximum HP gains or best fuel efficiency ... heck you could tune for best mpg below 3000 rpm AND max power above it, any way you want it, and would benefit whether you're just modded with bolt-ons or boosted. And could be reflashed back to stock if needed.

Won't happen though until someone hacks the ECU ...

 

^^DO IT!

 

Good luck....i believe its been deemed undo-able for now...

 

Quiet Debbie Downer, let him do it!!!

 

My question is,

Has anyone added anything to their car, and seen a bump in overall MPG? Of course, I hope you are recording your data regularly so its not just variable data. I have considered adding the TRD air filter. Has anyone seen any performance increase because of this?

 

No, "performance" drop-in filters are a waste of money ... won't give you any more HP or better mileage.

Like you I carefully document my mpg's at every fill-up. I've added a cold air intake, header, and exhaust and overall mileage hasn't changed for better or worse ... still comes down to how hard I drive and how often the highway becomes a crawl.

Honestly by buying a 4-cylinder fwd sub-compact and driving conservatively you've done about the best you can do to wring fuel economy out of an automobile ... even hybrids have been shown not to be a bargain unless you drive only in city traffic.

If you're still determined to improve mpg's you're pretty much limited to fringe methods like hypermiling (which is dangerous), adding wierd chemicals to your gas, and home-brewed hydrogen systems ... a friend just got the plans to build an on-board hydrogen system (justaddwater.com is the web site iirc) ... he's going to put it on his old Chevy van and see what happens ... supposed to increase your mileage up to 70% ... idk

 

Friction is the biggest enemy when it comes to gas efficiency. So with that in mind keeping the internal lubed up with quality oil is a start. Use synthetic oils for your engine and transmission will yield results. Lighten up the load on your car. It'll take less energy to get the car moving up hills or from a start. Lighten up rotating mass is even better. The theory is for every 1lbs of rotating mass, frees up 2hp for your car.
To help the pistons rotate more efficiently (for example pushing the exhaust out of the combustion chamber) a quality header and exhaust would aid in the flow of extracting fumes from the car. Also just like you and me the harder we run the more air we need to perform. Such is the same with your car. Inflated your tires a little higher than 35psi to help reduce rolling fiction. All this will help save mpg and I'm sure there are even more ways like an ECU reflash but it won't come easy and I'm glad this tread was posted to bounce ideas off each other.

 

Good Posts Everyone.

I think everyone should try and keep track of their gas mileage for a starter. If you start doing that you will see trends that you normally wouldn't see. If you want me to data crunch, just let me know ; )

I have started keeping tabs of time of day the gas is pumped. I haven't seen any trends thus far, but I will let you know if any show up.

I have seen a major seasonal trend. Where is everyone located? Can you post your location and the average temperature for the 4 seasons? Then post your MPG per season and maybe we can get a brief idea if temperature has a major effect or not.

 

i dont think its temp as much as it is road conditions.
(if you live somewhere with alot of snow and ice your tires will spin more when trying to accelerate up hills, etc...)

 

doesnt hot ac uses heat from the engine? thats more efficient than cold ac wouldnt it?

 

I live in texas, and we don't get snow very often. But I do see a difference in MPG.

Winter 07-08 : MPG = 26.575
Summer 08: MPG = 30.525

 

interesting.

 

This is normal where you have distinct seasonal changes (unlike where I live). Cooler (denser) air = ECU injects more fuel, more power but lower fuel efficiency at a given rpm ... similar to the effect of installing an intercooler.

 

1. Make sure your tires are FULL. I got 2-3mpg more out of my car at the tail end of my stock tires b/c I cranked the tire psi to the max rated on the sidewall. You won't believe how far you can coast with them at 50psi!!!

2. K&N filter, I say this with some reservations since I know many of you have full intakes but I have read up on how K&N goes to great lengths to make the filters as effiencient as possible WITHOUT giving the cars ECU a headache to deal with. If your wondering why it boosts MPG, it reduces the engines pumping loses of air coming in. Yes it should also boost a pony or two.

They do cost 50 bucks or so and that does buy a decent bit of fuel though.

dave