How do I increase MPG?
08-18-19, 12:27 PM
#31
08-22-19, 05:29 AM
#32
Tomorrow is the installation day for these plugs. I would like to post an unbiased review of immediate and short term effects (less than 2 weeks) of these ruthenium plugs, avoiding big claims, but rather seeing the changes observable BEFORE and after ECM adjusts to the new setup. I will also calculate the approximate fuel economy in percentages from the previous data. Finally, I will look at how transmission behaves, and will check the quality of engine operation. The latter will be mostly subjective, however, I usually distinguish different conditions and especially when I know that everything else has already been taken care of.
Note to Yodaone - just letting you know that there is a chance that I may disagree with some of your claims, so please take it as just an opinion.
Last edited by ls430w140; 08-22-19 at 05:37 AM.
08-22-19, 08:18 AM
#33
You can only RESTORE mpg, You can't increase it unless you are a machinist, engineer, and can reprogram the ecu tune.
That said you can restore factory mileage to a point...make sure ALL fluids connected to rotating parts are NEW; power steering, coolant, oil, differential, and transmission...and that they are as low viscosity as factory specs allow. Make sure spark plugs AND wires are new. Make sure the air filter and fuel filter are new. Other than that the only other factor is your foot and the type of roads you drive on.
Now I need new plugs, wires, tranny and diff fluid but;
flat interstate I get 25mpg
highway I get 23
most other roads I get 20-21
when I "cruise the loop" I get 18...because I lose some rubber here and there XD
That said you can restore factory mileage to a point...make sure ALL fluids connected to rotating parts are NEW; power steering, coolant, oil, differential, and transmission...and that they are as low viscosity as factory specs allow. Make sure spark plugs AND wires are new. Make sure the air filter and fuel filter are new. Other than that the only other factor is your foot and the type of roads you drive on.
Now I need new plugs, wires, tranny and diff fluid but;
flat interstate I get 25mpg
highway I get 23
most other roads I get 20-21
when I "cruise the loop" I get 18...because I lose some rubber here and there XD
08-22-19, 01:46 PM
#34
Lexus Champion
Has anyone replaced a component that lead to a huge increase in fuel efficiency/MPG? Currently getting 20 MPG max with all highway driving, about 17-18 combined. I see a few others have achieved 25-30 MPG. Any tips would be greatly appreciated. Bought my '04 LS430 at 140,000 miles, currently at 170,000 miles and not sure if the spark plugs were ever changed. I might try starting there.
If your mileage isn't good after your motor is in excellent tune, then you can do what the hypermilers do (don't actually do this stuff, but it will theoretically increase MPG)
.... tires at 50PSI, pulse and glide driving, driving without brakes, ignition-off in neutral to coast, 0w20 motor oil, really lightweight differential and gearbox oil, removing interior parts, remove air conditioning, moon hubcaps, full underbody shroud... Oh, and most importantly, don't drive over 55mph! 
The following users liked this post:
stuckincal (10-02-19)
08-22-19, 01:50 PM
#35
Lexus Champion
08-22-19, 03:49 PM
#36
Lexus Champion
Get a full tuneup.
If your mileage isn't good after your motor is in excellent tune, then you can do what the hypermilers do (don't actually do this stuff, but it will theoretically increase MPG) .... tires at 50PSI, pulse and glide driving, driving without brakes, ignition-off in neutral to coast, 0w20 motor oil, really lightweight differential and gearbox oil, removing interior parts, remove air conditioning, moon hubcaps, full underbody shroud... Oh, and most importantly, don't drive over 55mph!
If your mileage isn't good after your motor is in excellent tune, then you can do what the hypermilers do (don't actually do this stuff, but it will theoretically increase MPG)
.... tires at 50PSI, pulse and glide driving, driving without brakes, ignition-off in neutral to coast, 0w20 motor oil, really lightweight differential and gearbox oil, removing interior parts, remove air conditioning, moon hubcaps, full underbody shroud... Oh, and most importantly, don't drive over 55mph!
08-23-19, 06:47 AM
#37
So, last night I finished installing the ruthenium plugs in my 2006 ls430. I hoped so much to expect nice results, however, I must admit there are none. I highly suggest to stick with Lexus recommendation about standard plugs for this car which may last up to 100k miles.
It is much wiser to look at other things like presence of oil leaks in spark plug area, fuel injector contaminations, MAFs, quality of oil and filters. Check the existing condition of spark plug for any substances that shouldn't be there. If there is a dirt/oil or heating element, then its NOT the plugs, but OTHER things that play a bigger role in your "situation".
It is much wiser to look at other things like presence of oil leaks in spark plug area, fuel injector contaminations, MAFs, quality of oil and filters. Check the existing condition of spark plug for any substances that shouldn't be there. If there is a dirt/oil or heating element, then its NOT the plugs, but OTHER things that play a bigger role in your "situation".
The following 2 users liked this post by ls430w140:
bd3471 (08-23-19),
stuckincal (10-02-19)
08-23-19, 07:13 AM
#38
Lexus Fanatic
Man one way to increase mpgs is to get a new Nissan Altima. I had a new one in NC (200 miles on the odometer) and it was hard to get that thing not to deliver 40 mpg. Ridiculous. It's a full sized car. To illustrate the following week I got a Maxima, and that only did around 31. It is in no way worth the 9 mpg penalty, Maxima doesn't even have much torque.
08-23-19, 09:26 AM
#39
So, last night I finished installing the ruthenium plugs in my 2006 ls430. I hoped so much to expect nice results, however, I must admit there are none. I highly suggest to stick with Lexus recommendation about standard plugs for this car which may last up to 100k miles.
It is much wiser to look at other things like presence of oil leaks in spark plug area, fuel injector contaminations, MAFs, quality of oil and filters. Check the existing condition of spark plug for any substances that shouldn't be there. If there is a dirt/oil or heating element, then its NOT the plugs, but OTHER things that play a bigger role in your "situation".
It is much wiser to look at other things like presence of oil leaks in spark plug area, fuel injector contaminations, MAFs, quality of oil and filters. Check the existing condition of spark plug for any substances that shouldn't be there. If there is a dirt/oil or heating element, then its NOT the plugs, but OTHER things that play a bigger role in your "situation".
The following users liked this post:
bd3471 (08-23-19)
08-23-19, 09:47 AM
#40
Man one way to increase mpgs is to get a new Nissan Altima. I had a new one in NC (200 miles on the odometer) and it was hard to get that thing not to deliver 40 mpg. Ridiculous. It's a full sized car. To illustrate the following week I got a Maxima, and that only did around 31. It is in no way worth the 9 mpg penalty, Maxima doesn't even have much torque.
08-23-19, 09:49 AM
#41
I changed my plugs at about 125-130,000 miles with OEM plugs and it made no difference in performance or mileage. In addition they looked great for all those miles. I'm sure if they stayed in there till 200,000 miles all would be fine. I also changed and purchased a new MAF (Denso) from Rock Auto awhile back strickly because the car was so old and for the price why bother cleaning it? Again, no real difference in performance.
Have you checked the valve cover and spark plug gaskets? Are they still running leak-free?
08-23-19, 09:59 AM
#42
Driver School Candidate
Thread Starter
Nah nah nah. If y'all want fuel economy, wait til Late 2019/Early 2020 for Mazda to release their revolutionary Skyactiv-X engine which reportedly gets up to 55 MPG combined, pure gas (NOT HYBRID). It can switch between regular spark and diesel-style compression ignition. Someone take one for the team and be an early adopter.
08-23-19, 10:00 AM
#43
Changed both valve cover gaskets, spark plug valley gaskets, all grommets, PCV (not seal for fear of dropping a piece of brittle rubber inside of cover), dip stick 0 ring, and trans shifter bushings. Anything old and brittle I've changed including as many of the vacuum hoses for the EVAP system that I could find with OEM from the dealer. Our cars are old and everything in the engine compartment has been baking in there like an oven. The good is there are absolutely no engine or trans leaks anywhere and the under undercarriage is dry as a bone! PS. I am so damn **** I started coating rubber seals (around windshield) and other areas that have rubber with silicone for protection. I use a cue tip to keep things neat.
Last edited by Bocatrip; 08-23-19 at 10:04 AM.
08-23-19, 10:04 AM
#44
Lexus Fanatic
Yeah I don't know, just that since I am not pushing my rentals, I was OK with the Altima (would not buy because of the zero steering feel). The Maxima was peppier but think about this--my 1998 has 205 ft. lbs, and the 2019 is like 260? That's not very good of an improvement, plus 3 to 3.5 liters. The Maxima was nicer but dated imho. Love the radar cruise on both, however. There are times getting 19 mpg commuting is old. I mean any 2019 car is going to do 26'ish instead (if a 4 cyl, even if turbo)
08-26-19, 07:27 PM
#45
Lexus Champion