Gas Mileage!!!!

hey, i was just recently given about 700 bucks, and i was just wondering what i could get to boost my MPG!!!! the 3.50 a gallon isnt so fun anymore. well i was thinking intake and exhaust? thanks for puttin in the time to post!

i'm mechanically inclined, just money declined, so i dont want to buy something that wont help, and i have just about every tool, so thats not a problem either, thanks!!!

Make sure you are using a fresh air filter. You may consider getting an oil-wetted filter from TRD or AMSOIL. They are very efficient, reusable after cleaning and re-oiling, and somewhat expensive. They are free-flowing compared with efficient paper filters and you can clean them as often as you like. I clean mine every 10k. The TRD filter is oil-wetted cotton and the AMSOIL filter is oil-wetted double layered plastic open cell foam.

Tweak your AFM (on engines that have them instead of a MAF meter) as shown in:
http://www.automotiveforums.com/vbulletin/showpost.php?p=3320951&postcount=8
There is probably an optimum setting for gas mileage.

Some people get additional mileage from opening up the air box (deckplate mod or removing the wheel well elbow from the airbox).

I don't believe in cold air intakes. They are a waste of money IMO. Maybe some vehicles have poorly-designed intake systems and are helped by almost any mod. Yours is not one of them.

Your engine may get better mileage with higher octane gas, particularly if you do alot of highway driving. Use higher octane gas for a few tankfuls when you are on a trip, keeping track of the mileage and gas used, and see if that makes any difference. If not, don't waste your money. Say the price of 87 octane is 30 cents cheaper than 89 octane and you get 20% better mileage (from 15 mpg to 18 mpg) with the 89 octane. If the price of gas for the 87 octane is $3.00/gal, then you are paying 10% more per gallon, while saving 20% in gasoline usage. This is a good bargain. If you break even, I would still use the higher octane gas. You have to do the math and the experiment on your truck. At some price, it will be worth it for some percent increase in mileage. In all honesty, you probably won't see a difference in mileage between the octanes, meaning you should use 87 octane. However, it doesn't cost much to try and you should know about it if your truck derives a benefit from the higher octane gas.

Keep an eye on your ignition timing, idle speed, and wheel alignment. A high idle speed will cost you, as well as retarded ignition timing or bad alignment.

Buy road tires. Mud stompers will cost you. I believe that the more noise the tires make on the road, the poorer gas mileage they will give you. Fill the tires with 4-6 more psi than that recommended in your door label. Low tire pressure will cost you. Don't fill the tires above the maximum psi labeled on the tire.

Lowering your truck a couple inches will give you better mileage on the highway.

Off-road driving will cost you. 4WD usage will also cost you, on- or off-road.

Installing manual hubs will make some difference. Each truck will be different in this regard. Manual hubs will keep you from having to rotate the half-shafts and a part of your front differential.

Keep your injectors clean with a fuel additive periodically.

Get any "Check Engine" light problem immediately. Many times you engine will default to a standard condition when a sensor goes bad. It gets you where you're going, but it is far from optimum as far as engine efficiency goes.

Exhaust headers and lower restriction cat converters and mufflers will help your mileage to varying degrees. Buy stuff that you find has helped other 4Runner owners.

Fill your transfer case and differentials with 75W90 synthetic gear oil. Leave it in longer to partially offset the additional cost. The thicker the gear oil, the more drag on the truck. Lube your propellor shafts often for the same reason with Moly grease.

Use 5W30 oil in your engine - possibly 0W30 or 5W20. I have heard they work fine, but I have not tried them myself. Those lower viscosity oils will certainly make a difference in your gas mileage.

I'll add this to the FAQ - seeing how gas is getting precious. Any additions from other posters will probably be added also.

THANKS A TON!!! that helped a lot, i'm going to definitetly try the new air filter, and exhaust for now, and headers down the road (money) thanks for all that, in another 2000 miles, i'll need to change all my fluids so i'll take that in to consideration.

THANKS AGAIN! saved me 200 bucks on a k&N

You're welcome. Don't forget that there are many people who swear by those intakes. If you see independent dyno data from a truck just like yours and it shows an increase with the CAI and with no other concurrent mods, then go for it.

I was reading your gas mileage suggestions, and they were very helpful. I recently had my check engine light come on, and it was telling me my truck was running "lean". the diagnostics narrowed it down to the left bank of my engine. it has been idling high, and getting REALLY bad mpg's. I had a shop do a fuel injection cleaner & I purchased an O2 sensor (fron one only). my question is, what else should I try to help this problem? It's time for me to change my ignition wires... but is there better ones to buy, than others? will it make a difference? is there something else, that is fairly easy on the pocketbook, to replace to help my gas mileage & idling? thanks for all your help!

Welcome to the AF!

Go with Toyota wires. Unless you are having ignition problems, new wires probably won't help.

I've already pretty much said everything I can think of in the previous post.

stuff that I have annotated, posted, cut and pasted, for the past three to five years while attempting to get the most power AND the most mileage:
(some items may be duplicated)
most of this article is verbatim from:
the www.procarcare.com site written or edited by W. G. Nichols for the Chilton's Easy Car Care.
"Change the oil and filter as recommended. Dirty oil is thick and causes extra friction between the moving parts; cutting efficiency and increasing wear. Use a "Energy Conserving" type motor oil.
Radial tires have been standard equipment on most vehicles since the middle 80's. However, be sure the tires are properly inflated. Under-inflated tires can cost as much as 1 mpg. Better mileage can be achieved by over-inflating the tires (never exceed the maximum inflation pressure on the side of the tire), but the tires will wear faster and the ride will be rougher.
Replace spark plugs at regularly scheduled intervals. New plugs alone can increase fuel economy by 3%.
Be sure the plugs are the correct type and properly gapped.
Be sure the ignition timing is set to specifications.
If your vehicle does not have electronic ignition, check the points, rotor, and cap in your distributor as specified.
Replace the air filter regularly. A dirty air filter enriches the air/fuel mixture and can increase fuel consumption as much as 10%. Tests show one third of all vehicles have air filters in need of replacement.
Replace the fuel filter at least as often as recommended.
On carbureted vehicles, be sure the idle speed and carburetor fuel mixture is set to specifications.
On carbureted vehicles, check the automatic choke. A sticking or malfunctioning choke wastes gas.
Replace the PCV valve at regular intervals.
Service the cooling system at regular recommended intervals.
Be sure the thermostat is operating properly. A thermostat that is stuck open delays engine warm-up, and a cold engine uses twice as much fuel as a warm engine.
Be sure the drive or serpentine belts (especially the fan belt) are in good condition and properly adjusted.
Be sure the battery is fully charged for fast starts.
Use the recommended viscosity motor oil to reduce friction. Use "Energy Conserving" type motor oil.
Use the recommended viscosity fluids in the drive axle and transmission.
Be sure the wheels are properly balanced.
Be sure the front end is correctly aligned. A misaligned front end actually has wheels going in different directions creating additional drag.
Correctly adjust the wheel bearings. Wheel bearings adjusted too tight increase rolling resistance.
Install a flex-type fan if you don't have a clutch fan. Flex fans push more air at low speeds when more cooling is needed. At high speeds, the blades flatten out for less resistance.
Check the radiator cap for a cracked or worn gasket. If the cap doesn't seal properly, the cooling system will not function properly.
Check the spark plug wires for cracks and burned or broken insulation. Cracked wires decrease fuel efficiency by failing to deliver full voltage to the spark plugs.
=========

Avoid extended warm-ups. As soon as your vehicle is drivable, accelerate gently and slowly until the vehicle is fully warmed.
Avoid unnecessary idling. One minute of idling uses more gas than it takes to restart the engine. Prolonged idling uses gas at the rate of about ½ gallon per hour.
Avoid sudden stops and starts. Hard acceleration uses up to one third more gas. Achieve your desired speed with a steady foot on the accelerator and try coasting to stop.
Drive at a steady pace. Plan your route to avoid stop-and-start conditions and heavy traffic. Be aware of the traffic around you and adjust your driving to avoid constant acceleration and deceleration.
Many traffic light systems are "timed" for a given speed. Try to pace your speed to make the green lights rather than going faster and stopping for red or yellow lights.
Try to anticipate traffic jams and avoid them when possible. Despite stops for traffic signals on other roads, avoiding those expressway traffic jams can lower fuel consumption as much as 50%.
Choose your road surface. The fuel economy penalty for driving on soft or poorly surfaced roads can be 10-30%.
Avoid excessive braking. The need for braking can often be eliminated by downshifting or simply taking your foot off the gas.
Combine several short trips into a single trip. Short trips (fewer than 5 miles) don't let the engine reach its most efficient operating temperature. By combining numerous short trips, you can save on the total miles driven and take advantage of the vehicle's more efficient warmed-up condition.
On long trips, start early in the morning to avoid heavy traffic and to reduce the need for air conditioning in hot weather.
If you own more than one vehicle, use the most economical, especially for commuting or stop-and-go driving.
Use the transmission properly. If your vehicle has a manual transmission, shift gears as soon as the engine can run smoothly in the next gear. Low gear at 20 mph gives only about two-thirds the mileage as high gear at the same speed. In second gear, it's four-fifths the mileage you'd get in high. With an automatic transmission, lifting your foot slightly off the accelerator will make the transmission shift sooner.
When approaching hills, don't wait until the vehicle begins to "lug" before shifting gears. Don't accelerate once you have started up the hill, because speed increase is slight and gas consumption is high. You can minimize the speed loss by gradually increasing speed as you approach a hill.
If you can, take advantage of good weather, and avoid bad weather driving. Rain or snow can reduce gas mileage as much as 2 mpg. A strong headwind can mean a 10% loss in fuel economy.
Summer temperatures above 70°F (21°C) are better for fuel economy than winter temperatures. There is an approximate 85% difference in economy between 70°F (21°C) and 20°F (-7°C).
If equipped, use the cruise control. A cruise control can gain 1-2 mpg by maintaining a steady, preset speed over any kind of terrain.
The best fuel economy is obtained at moderate speeds. More fuel is consumed below 35 mph than at 45 mph, and generally, you'll lose 1 mpg for every 5 mpg over 50.
Use the A/C at highway speeds. Although the weight and operation of the air conditioner reduce economy, tests have shown that wind drag at 55 mph with the windows open can consume more fuel that using the air conditioner with the windows shut. The least efficient time to use the air conditioner is at lower speeds. Turn off the air conditioning, at lower speeds, and use the vents when the outside temperature is in the comfort range.
Don't carry unnecessary equipment in the trunk. Weight is the largest single factor in fuel usage, and every extra hundred pounds in cargo costs about 1% in fuel economy.
Don't load cargo on a roof rack. This just creates frontal area, increases air resistance, and lowers your mpg.
Learn to drive by instruments. Reading the tachometer (if equipped) can keep the engine in the optimum 1000-3000 rpm operating range. A vacuum gauge indicates the highest engine vacuum (best mileage).
Relax while driving. Find a comfortable driving position; fidgeting in the seat leads to constant speed changes and decreases gas mileage.
Avoid buying super-wide tread tires. They only create extra rolling resistance. Stick to the manufacturer's recommendations.
If you drive a manual transmission vehicle, start in second when going downhill.
On a 4-barrel carburetor engine, learn how to move the gas pedal to avoid activating the secondary circuit, except in an emergency.
Avoid using large mud-flaps or oversize rear view mirrors unless necessary. They only create extra drag (air resistance).
Don't drive fast until the engine has fully warmed to normal operating temperature.
In winter, clean accumulated snow and ice from the trunk, hood, and roof before driving. Carrying heavy, wet snow uses fuel.
Keep accurate records. Over a period, you can check your fuel economy; a sudden drop in miles per gallon may mean it's time for a tune-up or other maintenance.
==========
EFFICIENT DRIVING
1. Avoid aggressive driving habits like speeding and rapid acceleration. It lowers gas mileage by up to 33% at highway speeds. Gas mileage steadily decreases at speed above 60 MPH.
2. Avoid unnecessary idling. Vehicles get 0 MPG while idling.
3. Use the cruise control. Setting cruise control while highway driving maintains consistent speed and saves gas.
4. Use overdrive gears to slow down engine speed, saving gas and reducing engine wear.
5. Use the ventilator instead of the air conditioner and keep windows rolled up. This reduces engine workload and wind resistance, improving fuel economy up to 15 percent.
PROPER MAINTENANCE
1. Fixing out-of-tune vehicles improves fuel economy by an average of 4.1 percent. Replacing a malfunctioning oxygen sensor improves fuel economy by as much as 40 percent.
2. Regularly check the vehicles air filter. Replacing a clogged filter not only improves fuel economy by up to 10 percent, it protects the engine as well.
3. Check tires for proper air pressure every two to four weeks. Properly inflated tires improve fuel economy by about 3.3 percent.
4. Use the manufacturer's recommended motor oil viscosity. Using a higher viscosity than recommended decreases fuel economy by one to two percent.
GOOD PLANNING
1. Combine errands into one trip. Engines are most efficient when warmed up. Multiple short trips taken from cold start use up to twice the gas as one longer trip covering the same trip.
2. Avoid peak rush hours as much as possible to spend less time in traffic and consuming gas. Taking advantage of carpools, ride share programs, and public transit not only saves fuel, but wear and tear on vehicles as well.
3. Reduce aerodynamic drag by carrying cargo in the trunk rather than on a roof rack. This can improve fuel economy by five percent. Avoid carrying unnecessary heavy items. One hundred extra pounds in the trunk can reduce fuel economy by one to two percent.
=========
Watch your speed. For every mile per hour over 50, mileage decreases roughly one percent. When traveling at a steady speed, most vehicles get their best mileage between 35 and 45 mph. "

http://www.performancempg.com/lubricationnews/better_fuel_mileage.htm

http://www.procarcare.com/icarumba/resourcecenter/encyclopedia/icar_resourcecenter_encyclopedia_fuelsaving.asp

another site from an auto parts store:

http://www.pdqpartners.com/english/youcan/html/ccr/ccr20030101gm.html

and plenty more by doing general searchs on the net under fuel tips, gas mileage, fuel economy, etc.


hope this helps,
chris
nrt racing

The contents of the previous post can also be found at:

http://www.procarcare.com/icarumba/resourcecenter/encyclopedia/icar_resourcecenter_encyclopedia_fuelsaving.asp

http://www.performancempg.com/lubricationnews/better_fuel_mileage.htm

However, it appears that ctelsa was the original author of the posted material. He sent me a scanned image of an old pamphlet he authored from Champion auto parts with this information.

Good job ctesla and thanks for sharing.

I'm curious. With all the talk about increasing gas mileage, just what is the gas mileage most people are getting? I have a 2002 PreRunner Xtra cab with the TRD package and 2.7 litre engine. I have been able to average about 23mpg give or take .5gal. How does that compare with what others have been getting? Over the last year I have been able to increase my gas mileage from an average of 19. Some things that have helped:

1. Moved to Denver. The thinner air requires less fuel to achieve the proper combustion mixture.

2. Replaced the air filter with an AC Delco that was rated well in another thread. See post 6.
http://www.automotiveforums.com/vbulletin/showthread.php?t=376692&highlight=filter

3. Bought an aftermarket locking gas cap. Interesting thing is that when my truck and the girlfriends SUV went for emissions checks, mine passed with flying colors on all tests, she was told to replace her stock fuel cap. Apparently it didn't seal properly. Also prevents gas theft since Toyota's fuel doors don't lock.

4. I run my tires about 3-4 psi above recommended on the inside of my door. Also check them about once a month.

5. I drive more conservatively, not accelerating hard and not staying on the gas as I head towards a red light. I also watch the tach more carefully and try to keep the RPM's as low as possible. 1800-2000 seems to work well for most roads around 40 to 45mph.

6. I've found another way to work that has cut about 6 stoplights from my route. My job fortunately has me travelling at off-peak times so I don't hit rush hour traffic. If I have to hit the store, I do it on the way home since I pass it anyways, even if it is for only 1 or 2 items. Other errands are all consolidated as much as possible. The toyota dealership is right near my work, so I booked the ball joint replacement for right after work early in the morning. I figure that will save about 18 to 20 miles of driving right there.

7. Bought a bike and ride or walk for several errands now. Gotta save that gas money for ski season.

...and I know how everyone hates to be preached to concerning preventative maintenance; HOWEVER, the biggest fuel stealer, or "highway robber" as I like to call it (other than an actual's driver's habits) is:

your own vehicle!

on our own dyno tests starting with a 355" SBC on the bench, and installing and attaching sensors and probes, step-by-step hooking it up into a fully functional car,
the transmission and driveline immediately starts turning your gross horsepower into net...
their is an 18-25% loss in power/economy before it even hits the differential.
the rear end killed another 10-15%,
air conditioning and other accessories robbed another 1-3%,
and once all together, and rolling around the speed shop in mediocre stop and go Denver traffic, we figured about another 15-20% loss from various dynamics of driving (tire psi, actual contact with road surface, roll resistance, brakes, drag coefficients) and probably a whopping 20% in just idle time (remember the formula: 0(zero)mph=0(zero)mpg!)


warm air induction for economy good,
cold air induction for power good.
if you are not set on lo profile tires, the smaller the amount hitting the pavement, the less resistant; so good tread and maybe a 235/ 75 R15 instead of a 235/ 70or60 R15.
and lube propshafts! or replace u-joints, and drain and fill transmissions (YES EVEN manuals!) and replenish with a synthetic or conventional w/additives.
if you have a stick (or auto) and have well developed driving skills; if you see traffic or a light ahead, pop it in Neutral and coast to stop, or feather the brakes, and see if it clears before you get to intersection, or traffic, as once stopped you have to utilize 100% fuel to power ratios to achieve rolling inertia again.

...
if you are an excellent and exceptional driver(and have a good starter), you could even kill the motor; saving fuel AND placing zero resistance on the rolling vehicle to achieve greater distance with NO POWER!

disclaimer:
(I DO NOT RECOMMEND OR CONDONE THIS BEHAVIOR, as shutting off the engine will reduce vacuum to assist with power brakes, and also shut down power steering (if equipped), and also certain vehicles have locking steering wheels, which even if only clicked to assy, rather than the key in off or ignition, could cause the wheel to lock, not allowing a driver to waiver from given course of travel!)...

but, I can honestly say that the thing I said you shouldn't do does assist in the market 3-5% additional miles per tank depending upon climate, traffic conditions, driving habots, etc. this ended up as only about 18-20miles. you can shave that off, by calling in sick once a month, or planning a more concise way of travel, etc.
overall, it wasn't worth it, as this experiment was in an automatic german vehicle, so steering locked, lost partial braking and steering, had to shidt into Park again to restart, so the inertia thing, ocassionally had to remove key, to reset, had to reset A/C controls, etc...
I could see it if you were more rural, with only slight traffic problems, but I really wouldn't go to this extreme, not just because of safety, but how many of us actually like changing starters!

hope this helps,
chris
nrt racing

I'm curious. With all the talk about increasing gas mileage, just what is the gas mileage most people are getting? .


'02 Tacoma PreRunner 2WD, auto, 2.7L doublecab.
265/70R16, Bosch+4, injen air intake, K&N cone
A/C ALL the time (currently in Houston)

20-22mpg

in Denver, 22-25mpg (a/c not all the time?)
and not as much humidity in the air/fuel mix

chris

04 dbl cab V6 trd auto, 17,500 miles on engine and plugs and wires, air box elbow removed,amsoil air filter, mobil 1ss oil and filter and the most expensive amsoil differrential fluid (like $7 or $8 a qt. with the discount and its green and smell like roten eggs) oh yeah tires:265/70/16 29 psi......I average like around 21 mpg driving along with traffic with ac on rarely

04 extra cab 2.4 engine with automatic, 205/75/15 tires, everything is stock with about 14k miles.
22-25 mpg for highway driving. AC doesn't seem to make a lot of difference. I use 5w/30 dino oil.

Clifton