Poor fuel mileage
- Thread starter NJacob
- Start date
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How bad?
Mike6158
Random Pixel Generator
My mileage is only bad when it's running. Around 12 mpg or less.
Is it stock or lifted and modified? I get 9MPG city 12hwy but my Cruiser is modified. Off the top I would check air filter, clean throttle body, check tire pressure, pour some fuel injector cleaner in the gas tank, when was the last time your spark plugs where changed? Oh yea, and lay off the gas pedal.... 
all things considered 12mpg isn't bad, I was getting 14mpg stock.
all things considered 12mpg isn't bad, I was getting 14mpg stock.
My car is basically the same as yours and it gets similar fuel mileage. 4.5 and Auto
I get 10 miles per US gallon (3.78 L) in the city. On highway at 77 mph, I get 12.7 to 13.9 mpg. Truck is stock, 4.7 V8 auto.
You think you get bad mileage? Here is a 100 series mileage chart:
4-8 mpg Could be problematic unless you are making speed runs or towing something.
9-13 mpg pretty average depending on load, terrain, weather, vehicle equipment, and fuel quality.
14-19 mpg pretty much poop your pants good mileage or you are always going down hill.
19-24 mpg This would be a unicorn or a math error of some sort re check.
4-8 mpg Could be problematic unless you are making speed runs or towing something.
9-13 mpg pretty average depending on load, terrain, weather, vehicle equipment, and fuel quality.
14-19 mpg pretty much poop your pants good mileage or you are always going down hill.
19-24 mpg This would be a unicorn or a math error of some sort re check.
TrekboxX
Supporting Vendor
Dead nuts accurate. You'll hear some on this forum talk about their 18mpg or whatever. It's total BS. I even offered a large sum of cash to one such owner for his LC if it really did get that type of mileage. Guess how that worked out? Yup. Negative response.
Just drive it and don't worry about it.
Guys when you say clean throttle body can someone post the process. Thanks
Here's how I clean the throttle body and mass airflow sensor (MAF). You'll need a can of throttle body cleaner, MAF cleaner, a toothbrush and a clean lint free rag (i.e. old T shirt) or chux dish clothe. Flash light (torch).
1.Disconnect negative battery terminal and position it so it can't flip back on to the battery and make a connection/spark.
2. Loosen the compression clamp holding the plastic intake plenum to the alloy throttle body, 10mm bolt/philips head. Wriggle the plastic plenum off and prop it up so you can access the inner body and the butterfly valve.
3. Gently rotate the upper half of the butterfly in (counter clockwise) towards the dash with light finger pressure until the valve disc is almost horizontal- don't force it and don't go past horizontal. Now you can either hold the valve disc open in this position with one hand whilst squirting cleaner on the valve disc, its rim, back and the accessible sections of the inner body or you can carefully prop it open with a clean soft wedge in the bottom section - I have a section of a clean paint stirring stick about 30mmx5mm and 75mm long that's a perfect fit to hold the butterfly disc open almost horizontal without forcing it. Either way spray cleaner on the accessible inner surfaces and you'll see the oil blackened film start to lift, carefully scrub with the brush and wipe as you go. Wrap the cloth around the brush to get better, deeper access. The aim here is to remove the oily film that builds up on the butterfly valve, its rim, its backside and the inner surfaces of the throttle body without any undue force on the delicate valve or its pivot. Inspect your handiwork with the light, ensure you've not left any foreign body, fluff etc and then put the plenum back on and tighten the clamp.
4. Clean the MAF by disconnecting its connector, two Phillips head screws and it lifts off. Liberally spray down the wire filaments with MAF cleaner without touching them as they will break and render the sensor U/S. confirm the filaments are free off any foreign matter and look clean then reinstall making sure the O ring seal seats properly. Gently re tighten 2x screws and reconnect.
5. Reconnect battery and start. Expect a slightly longer, possibly labored start as the ecu trims/non volatile memory settings have been erased (after about 10 minutes battery disconnect, not sure exactly how long it takes but 10 + minutes seems to work) and the upper engine has just huffed a little hydrocarbon cleaner too.
6. Let it idle to hot/normal operating temp to settle down and repopulate the non volatile memory settings that were cleared with the battery disconnect.
1.Disconnect negative battery terminal and position it so it can't flip back on to the battery and make a connection/spark.
2. Loosen the compression clamp holding the plastic intake plenum to the alloy throttle body, 10mm bolt/philips head. Wriggle the plastic plenum off and prop it up so you can access the inner body and the butterfly valve.
3. Gently rotate the upper half of the butterfly in (counter clockwise) towards the dash with light finger pressure until the valve disc is almost horizontal- don't force it and don't go past horizontal. Now you can either hold the valve disc open in this position with one hand whilst squirting cleaner on the valve disc, its rim, back and the accessible sections of the inner body or you can carefully prop it open with a clean soft wedge in the bottom section - I have a section of a clean paint stirring stick about 30mmx5mm and 75mm long that's a perfect fit to hold the butterfly disc open almost horizontal without forcing it. Either way spray cleaner on the accessible inner surfaces and you'll see the oil blackened film start to lift, carefully scrub with the brush and wipe as you go. Wrap the cloth around the brush to get better, deeper access. The aim here is to remove the oily film that builds up on the butterfly valve, its rim, its backside and the inner surfaces of the throttle body without any undue force on the delicate valve or its pivot. Inspect your handiwork with the light, ensure you've not left any foreign body, fluff etc and then put the plenum back on and tighten the clamp.
4. Clean the MAF by disconnecting its connector, two Phillips head screws and it lifts off. Liberally spray down the wire filaments with MAF cleaner without touching them as they will break and render the sensor U/S. confirm the filaments are free off any foreign matter and look clean then reinstall making sure the O ring seal seats properly. Gently re tighten 2x screws and reconnect.
5. Reconnect battery and start. Expect a slightly longer, possibly labored start as the ecu trims/non volatile memory settings have been erased (after about 10 minutes battery disconnect, not sure exactly how long it takes but 10 + minutes seems to work) and the upper engine has just huffed a little hydrocarbon cleaner too.
6. Let it idle to hot/normal operating temp to settle down and repopulate the non volatile memory settings that were cleared with the battery disconnect.
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Really any v8! Even the newer 5.7 gets the same. Even the venerable ecopoop v6 gets the same. All comes down to weight and tires and any gas powered rig will get what we get.
Funny thing is when I was working at Toyota the people that bitch the most about bad mileage are Prius owners! Seriously, I used to say it must really be a harsh realization you traded your plush ride for an econobox and your still not happy with your mileage. Would you like to buy your truck back?
There is more to life than good gas mileage!
100 series fueling procedure:
1. Open fuel door
2. Insert nozzle start fuel flow
3. Check oil and fluids
4. Admire your top of the line best of everything go anywhere vehicle
5. Replace fuel nozzle taking care not to look at the pump screen
6. Drive away
You will realize after following this procedure for a while that you focus more on how much you really love your 100 and that mileage just does not matter. Stopping for fuel more often is a benefit to your physical safety and more frequent toilet brakes for your passengers so look on the bright side!
YardPig
SILVER Star
I know I shouldn't open this debate but are people noticing better fuel economy or more power running premium? I have always run regular, am I missing something spectacular?
I believe this is a myth.
Can you share what mileage you're getting currently?
^^^^ as JayM said
"100 series fueling procedure:
1. Open fuel door
2. Insert nozzle start fuel flow
3. Check oil and fluids
4. Admire your top of the line best of everything go anywhere vehicle
5. Replace fuel nozzle taking care not to look at the pump screen
6. Drive away
You will realize after following this procedure for a while that you focus more on how much you really love your 100 and that mileage just does not matter. Stopping for fuel more often is a benefit to your physical safety and more frequent toilet brakes for your passengers so look on the bright side!"
EXACTLY! The truck we all are driving will take you home safely and surely. I fill up the tank every 150-180 miles (2 hours) so all get a time to relax.
"100 series fueling procedure:
1. Open fuel door
2. Insert nozzle start fuel flow
3. Check oil and fluids
4. Admire your top of the line best of everything go anywhere vehicle
5. Replace fuel nozzle taking care not to look at the pump screen
6. Drive away
You will realize after following this procedure for a while that you focus more on how much you really love your 100 and that mileage just does not matter. Stopping for fuel more often is a benefit to your physical safety and more frequent toilet brakes for your passengers so look on the bright side!
"EXACTLY! The truck we all are driving will take you home safely and surely. I fill up the tank every 150-180 miles (2 hours) so all get a time to relax.
12 mpg sounds about right for a 2000 LC (4.5 or 4.7). My 01 LX 4.7 gets about 11-12 city, 14-15 hwy. My 01 LC was slightly less in mpg, but I ran 87 octane in it. Difference was less than 0.5 mpg. Premium (93 octane) seems to give a slight torque and HP boost. In winter, the mpg can drop a bit because of the winter gas formulation.
