Quest For Better Mpg

[Elronse]

This is my second post, the first was similar but wasn't specific to MPG only.

I have a 96 ES300 with 92k on it. It's in great shape and I want it to last for a good many years. The last vehicle I had was a little beater (95 Hyundai Elantra) that had 183k on it when I got rid of it. I figure if I can get that out of an Elantra, I should get 1 or 2 million from my Lexus. (Well 500k anyway).

Currently I'm getting 25.5 MPG. I improved it by .7 MPG by ensuring full tire inflation (Was SEVERELY underinflated on 1 tire).

As I put 25k a year on my car and gas prices are rising so fast, I'm on a quest for improved mileage.

Here's what I've decided to do and I'm interested in 2 things from you. The first being any warning or suggestions on what I want to do. If it's stupid, tell me. But tell me WHY it's stupid. The second being suggestions on what I can do in other areas to improve it more.

I am interested in a 1 year ROI on anything I do to the vehicle. As an example, if I do something that improves my mileage from 25 to 27.5 MPG, that would mean that my annual gas usage went from 1000 gallons to 909.1 gallons. Which means that the improvement must cost less than $163.62 installed. (90.9 gallons * $1.80 a gallon for premium).

So, first on my list is an improved air intake.

I have a K&N filter on order, this may or may not improve gas mileage. I plan on tracking this as well as I can, with notations on why I think mileage changed. I figure if I'm going to drive this vehicle until 2020, a reuseable filter is a must. Are there other filters that I can get the same kind of reuseability from for a similar price premium? I'm talking other filters in the vehicle.

I'm looking into installing a CAI. I can't find one for the ES300. Is there truly a space issue as I've read in several places? Or just not the market for it because it's not a performance / sports car?

Next on the list is to use AMSOIL 0w-30 with either an AMSOIL oil filter or a K&N filter. I like the idea of 'extended drain' oils. This seems anathema to me, but their literature convinced me as well as some 3rd party articles that I've read. They also have the ability to put 2 filters in place with one the normal full-flow filter and the second is a finer filter. As I'm planning on having this vehicle for a very long time, I figure the better the oil is filtered, the better off I am. Transmission fluid and gear box replacement fluids they make as well. All of these?

Exhaust is another that I may or may not get to. All I'm worried about is gas mileage, not horse power. However, I figure an engine that is a efficient as possible, will naturally get better mileage.

I've seen some CAT back systems that seem to be well-designed, and some full systems as well. How about a replacement CAT? I do know that a higher flow CAT can increase performance, but by how much?

And would that meet my ROI requirement. I would consider a longer period on the return on investment, but it would have to be a significant improvement in my mileage to make it worth the investment.

Any other suggestions?

Thanks,

Elronse

[bartkat]

You'll need to set your payout time. It probably should be the expected length of time you epect to keep the car. The ROI (return on investmen) would be the % returned. If you end up with zero ROI or any positive number, then you are ahead of the costs.

CAI isn't probably going to help MPG. The K&N you already have ordered will help a little. You really need to test that as your only mod, till you have the data on that.

Exhaust might help MPG a little, but it's an expensive item.

I think the extended change intervals for Amsoil are over hyped. Using a Castrol or Mobil synthetic should do just as well, since your car already has some miles on it. Most of the premium oils are "gas saving", but the difference may be too small to measure.

As for the dual oil filter, that's not going to help MPG, and with such an installation you are iinviting the chances for leaks and other problems. I don't know what it costs, but the payout may not be there, even if you do go with the extended oil changes.

The only thing that I can see that would really boost MPG would be a change in the differential gearing to a higher (lower numerical) gearing, allowing your car to run at lower RPM on the highway and in top gear. I don't know if such is available, but that would be the biggest change you could make. IMHO

[SpeedRacer959]

The K&N filter will probably make the biggest difference....helps the engine breath better. W/ dirty air filters, you get poorer mileage so it makes sense that w/ a clean air filter that is designed to give more air flow you'll get even better mileage.

Make sure you have good PSI in the tires at all times. Maximum PSI for maximum gas mileage. Ever ride a bike w/ low PSI in the tires? It makes a huge difference.

I don't see the pay off (ROI) w/ gearing, plus you might hose up your tranny.

I would think just keep it in optimal running condition...new spark plugs, K&N filter (clean), and you sould get optimal MPG.

Oh, you may want to get a professional fuel system cleaning. (~$80-$100) and it's reported to a MPG improvement on higher mileage cars...like mine and yours.

Blake918 (on the LOC board) is having his car fuel system cleaned and you could ask him if it makes a difference.

Let us know what you come up w/. I also ordered the K&N filter and will check the difference it makes. It's been reported to make around a 3 MPG improvment.

[steviej]

At 25.5 mpg, you probably won't squeak out much more. You fail to mention if this is combined, city or just highway. If it is soley "around town" anything you squeeze out after this is sauce for the goose.

Although not stated, my impression from your post is that you are already using 87 octane, right?

Good possibilities to try for instant ROI and most definately will save on overall maint. costs in the long run.

Use Mobil 1 synthetic 10W-30 for high mileage vehicles. Get it on sale and in the 4 or 5 qt jug (usually around $18 at wal-mart)

Use Toyota OEM filters and buy them in bulk from www.irontoad.com. Change oil and filter every 5k miles.

Drop in a bottle of Chevron w/Techron fuel injector/system cleaner every other oil change. Can't hurt/can help and only cost $5.00 bottle.

K&N drop in filter is awesome but can be variable. I personally picked up 3mpg city driving, some have actually had decreases. But is saves from ever having to buy a paper filter again. Don't bother with the CAI, you may forfeit MPG with the reworking/repositioning of sensors.

Properly inflate you tires. I run at 32 psi for stock tires and 40 for the low profiles. Check every other week or once a month.

Synthetic tranny fluid is another remote possibility but may not yield much of a ROI in one year as the benefits may be realized with lack of tranny maintenance in the long run.

Lastly, buy a bicycle and use it for any trip that is less than 3 miles. :chairshot:

good luck

steviej

[blake918]

I had my injectors flushed out at a Toyota dealer; I think it costs something like $60, but they have to change your oil at the same time too, so add around $25. I had this done in hopes of solving some vibrations that I feel comming through the steering wheel. Unfortunantly, I'm not too satisfied with the results; maybe I need a new motor mount or something(it seems like I read a lot about these on here)? I just filled up, so I'll let you know if that helped my mpg. Stevie what were your "decreases?" I'm looking to buy a k&n filter too; I didn't know there were some draw backs <_< ?

[steviej]

skperformance stated in an old thread that he did not have good luck with the K&N drop in filter in his application. I would direct your question to him to find out what decrease in mpg he observed.

steviej

Personally I say go for it. you cannot lose anything.

[ProZac]

Hey, you are getting GREAT gas mileage! i have a 97' with about 80k miles on it, and i am only getting 16mpg. YUP! 16miles per gallon, and it sucks When 91 octane gas is $2.32 US dollar it cost me $36 to fill up 16 gallons. California is sucking right now. I don't drive freeways much, mostly streets, and when i AM on the freeway there is stop and go traffic. Ive done fule treatments etc. but i believe because i am a city driver and i don't stay at a steady pace on the roads, my mileage suffers.

Be thankful for what ya got!

~ProZac~

[Elronse]

Thanks for all of the input. It's been a great help. Steered me away from a CAI for one. It makes sense what you said about it.

I'll definitely get a fuel system cleaning, but I won't do that until I have 2 or 3 tanks on the K & N filter. I want to see what it can do for me. I know that these things can be subjective. But my driving is constant with minimal variables.

I'll report any changes in MPG positive or negative from what I've tried.

Most of my driving is on the Interstate at 75 MPH. I have 45 miles one way with 80% of it at 75. Only 3 of the miles is non-interstate.

Thanks again.

[SKperformance]

my drop in filter made no difference in gas mileage

but i usually always aired out the filter once a month with compressed air anyway

but i was more or less only getting it or a performance improvment

[steviej]

Elronse, now that you state that the 25.5 mpg is 80% highway, then your mileage is pretty much what we get. The K&N will give you a boost most likely. I am getting 29-30mpg with straightout highway runs, 70mph, cruise control.

steviej

[m2pc]

You guys are getting great mpg! I drive 60% highway but get only 23 MPG on a 98 es300.

[Elronse]

I'll look into the tranny fluid. Even though it doesn't meet my stated ROI, it will definitely pay off in the long run.

Speaking of that. Anything else I should be doing / using to achieve longevity in my vehicle that may not be obvious? No ROI considerations.

And I consider the tranny fluid not to be obvious.

Thanks again,

[steviej]

yeah,

sit back, relax, roll the windows down, crank the tunes and just enjoy your Lexus for the smooth ride that it is.

Stop worrying so much about ROIs. Life is too short.

Now have some fun before it snows.

steviej

[Elronse]

Yeah, that's too true.

But, I do want to enjoy my Lexus for many more seasons.

I shall enjoy the ride, my friend. I shall.