Hello all since gas has gone to astronomical prices I thought I could make a game out of it called "Chasing MPG in my 80 series Lx450" How I increased my gas mileage.
My 80 for the last 2 years has basically just has been getting me to work & back, it did pull the 25' foot trailer 2 hours South two times last year. The gas mileage has dropped down to around 220 miles per tank fill up generally clicks @ 22 gallons after the light. So we are going to start with 10 MPG as my base.
Also lets get some facts out of the way:
4:88 gear & 37s come out to .5% over. Checked it many times with GPS trackers & the main one is Google maps it shows speed & distance. My speedo is off about 1 mile per 200 miles. I do have the 10% UD gears but it does not effect the speedo. I run 89 octane Chevron gas. I have a 97 Lx450 OBD2 with an Ultra gauge. My commute is about 5.2 miles to work 10.4 total commute. Have 3 stop signs through my small town & country road the rest the way to work.
Also to note the stuff I did below is what I did & by no means am I telling you legally what to go do to your vehicle.
So all that out of the way let's have some fun...
Like I wrote we are starting at 10 MPG. The 1st things I did is common knowledge for fuel economy like airing up the tires to full psi, using braking less, coasting & I took out about 200 pounds of stuff off/out of the rig. Also the Ultra gauge taught me that quicker accelerations to speed then hitting "cruiser" control ASAP got more efficiency. All that & only really got me about 11.5 mpg.
Now your say all that for 1.5 MPG? Yes we are building Rome brick by brick.
Another one of my issues is my rig gets to temperature about half way to work so the ECU is running in a limp/rich fuel mixture giving bad fuel mileage. If I drive the long way I get better MPG but use more gas.
2nd thing I did was reduce vacuum leaks from the manifold. I replaced a few hoses not holding vacuum, one was my brake booster (my brakes work much better now), the largest one was the PCV valve, so I plugged it off...yep plugged it off. I also added a inline oil catcher to the vent line since any blow-by will now go up that way then dump in front of the throttle body valve. This way the crankcase fumes will still be sucked through the manifold but wont cause a big vacuum leak in the manifold. Make since? The goal is the more vacuum the better chance fuel turns from liquid to vapor.
This increased my fuel mileage by approx. 1 mpg. At this point I was getting a solid 12.5 mpg after 94 miles of daily driving.
3rd thing was adding heat blankets on exhaust to send more heat to the front Cat o2 sensor A warmer o2 sensor will send less fuel through the engine if the cat is hot enough. This helps in my MPG in my short commutes because it gets the o2 sensor out of a rich fuel mixture mode sooner. They also have helped lower engine bay heat. I bought 3 of the 9" strait blankets plus a 3" 45 degree blanket. CXRACING HEAT WRAP / HEATSHIELD $35 each.
This got a solid 1 more MPG with 41 miles of daily driving.
The 4th thing didn't necessarily help MPG but is one step to reducing heat under the hood & reducing the risk of blowing another head gasket.
HuddExpo sells a "EGR Test Plug Kit".
The 5th thing I did was replace my 41K mile plugs for a set of hotter burning Pulstar Plasma Spark Plugs. (IBE1H10) fits 1FZ-FE 4.5L fzj80 $15 per. I was hoping for more than 1mpg, but was told that it sometimes takes up to a full tank of fuel to get better results. I have not done cap & rotor yet mine still looks good, I can do it later.
1 step at a time & document...
At this point I am getting excited because there is more things I'm working on that hopefully will give even more results.
Stay tune & Happy Trails to you.
Edited later:
People wanted old school calcs..
Here is a 13.6 mph well actually 13.5 if go out 3 decimals
My 80 for the last 2 years has basically just has been getting me to work & back, it did pull the 25' foot trailer 2 hours South two times last year. The gas mileage has dropped down to around 220 miles per tank fill up generally clicks @ 22 gallons after the light. So we are going to start with 10 MPG as my base.
Also lets get some facts out of the way:
4:88 gear & 37s come out to .5% over. Checked it many times with GPS trackers & the main one is Google maps it shows speed & distance. My speedo is off about 1 mile per 200 miles. I do have the 10% UD gears but it does not effect the speedo. I run 89 octane Chevron gas. I have a 97 Lx450 OBD2 with an Ultra gauge. My commute is about 5.2 miles to work 10.4 total commute. Have 3 stop signs through my small town & country road the rest the way to work.
Also to note the stuff I did below is what I did & by no means am I telling you legally what to go do to your vehicle.
So all that out of the way let's have some fun...
Like I wrote we are starting at 10 MPG. The 1st things I did is common knowledge for fuel economy like airing up the tires to full psi, using braking less, coasting & I took out about 200 pounds of stuff off/out of the rig. Also the Ultra gauge taught me that quicker accelerations to speed then hitting "cruiser" control ASAP got more efficiency. All that & only really got me about 11.5 mpg.
Now your say all that for 1.5 MPG? Yes we are building Rome brick by brick.
Another one of my issues is my rig gets to temperature about half way to work so the ECU is running in a limp/rich fuel mixture giving bad fuel mileage. If I drive the long way I get better MPG but use more gas.
2nd thing I did was reduce vacuum leaks from the manifold. I replaced a few hoses not holding vacuum, one was my brake booster (my brakes work much better now), the largest one was the PCV valve, so I plugged it off...yep plugged it off. I also added a inline oil catcher to the vent line since any blow-by will now go up that way then dump in front of the throttle body valve. This way the crankcase fumes will still be sucked through the manifold but wont cause a big vacuum leak in the manifold. Make since? The goal is the more vacuum the better chance fuel turns from liquid to vapor.
This increased my fuel mileage by approx. 1 mpg. At this point I was getting a solid 12.5 mpg after 94 miles of daily driving.
3rd thing was adding heat blankets on exhaust to send more heat to the front Cat o2 sensor A warmer o2 sensor will send less fuel through the engine if the cat is hot enough. This helps in my MPG in my short commutes because it gets the o2 sensor out of a rich fuel mixture mode sooner. They also have helped lower engine bay heat. I bought 3 of the 9" strait blankets plus a 3" 45 degree blanket. CXRACING HEAT WRAP / HEATSHIELD $35 each.
This got a solid 1 more MPG with 41 miles of daily driving.
The 4th thing didn't necessarily help MPG but is one step to reducing heat under the hood & reducing the risk of blowing another head gasket.
HuddExpo sells a "EGR Test Plug Kit".
The 5th thing I did was replace my 41K mile plugs for a set of hotter burning Pulstar Plasma Spark Plugs. (IBE1H10) fits 1FZ-FE 4.5L fzj80 $15 per. I was hoping for more than 1mpg, but was told that it sometimes takes up to a full tank of fuel to get better results. I have not done cap & rotor yet mine still looks good, I can do it later.
1 step at a time & document...
At this point I am getting excited because there is more things I'm working on that hopefully will give even more results.
Stay tune & Happy Trails to you.
Edited later:
People wanted old school calcs..
Here is a 13.6 mph well actually 13.5 if go out 3 decimals
Last edited: