Any explanation for a sudden increase in MPG - I'll provide a brief history on things that have changed leading up to a sudden increase in MPG.

2 Weeks Ago:
New tires - went from stock Dunlops to Hankook Ventus S1 Evo
New NGK Spark Plugs
Oil Filter + Oil Change

Went through two tanks of gas and stayed steady at ~17-18 MPG with 75% Hwy and 25% City driving.

AFTER the two tanks @ ~17-18 MPG:
I cleaned the MAF

Nothing else has changed (driving style, Hwy/Cty driving ratio, etc.) and my MPG has increased to 22 MPG (I'm easily getting 300 miles before the low light gas comes on versus the 240 miles I was getting previously before the low light gas comes on).

I'm wondering if changes such as Spark Plugs and Oil changes involve a "break-in" period which would help explain a sudden increase in MPG? I know the tires have a 500 mile break in period which could attribute to the increased MPG (just theorizing). However, cleaning the MAF resulted in an immediate change in MPG. Could cleaning the MAF explain this increase in MPG? I'm at a loss (not complaining though!).

EDIT:

Link to the pictures of my previous spark plugs
https://www.rx8club.com/showthread.p...52#post3002152

 

yes

 

Yes to which one of my questions? =P

 

yes

 

My bad. Location added.

Would there be a delay in the MPG increase after the installation of a new set of spark plugs?

 

maybe,

the ecu has to learn the new rules.

beers

 

you live in LA and you only drive on the highway in 6th gear?

 

I live in LA but I'm out in central California right now for extended training.

 

yeah plugs and MAF shold help the MPG....gotta do my plugs/coils withing the next 3 weeks..i'm at 45k miles.....takes a little becuase the PCM's adaptive learning will take a bit of time to learn that the a/f is burning better etc etc

 

That highway driving is a plus as well...When I drive to my drill in Birmingham (about 4 hours away), its all interstate the entire way. I can go almost 300 miles on a tank of gas and thats cruising at 70mph. Im sure if I did some of the change outs such as the spark plugs and new tires like you did, it would be a little better. Plus I found out that when your on the interstate, if you put the cruise control on and just go with it, it helps on the MPG's as well. Just got to watch out for those ****** who like to run beside you in the fast lane just when your about to get over and pass the car in the slow lane, which forces you to slightly brake. But hey what can you do.

 

Man I wish mine could do more than 170miles a tank lol

 

Lol, less gas pedal, more cruise control. and that doesnt mean hit the acceleration button either

 

I always use cruise

Oh well, I didn't get an 8 to boast about getting 500 miles to the tank

 

so what product and technique did you use to clean the maf with?

 

^damn 170 i get that if i'm into it alot or sitting in traffic a ton but luckily i leave early enough in the morn (5am) to stay out of traffic for the most part.

 

I used Radio Shack "Precision Electronics Cleaner". Disconnected the negative terminal on my battery, pulled the MAF and gave it a spray. The spray dries in seconds and once the black film on my MAF was gone I reinstalled everything. Took ~5 minutes to do everything.

 

I think cleaning the MAf is a great idea, but I personally believe that you should only mess with it if you have problems rough idling or some such problem.

 

Ha ha... Sumer gas is comming out now so you may the good stuff in the tank.

 

congrats

 

Well you didn't see a sudden increase in MPG. It was a slow decrease in MPG till you fixed all the MPG robbing issues.

 

Hmm lets see what happens with me... I was getting about 14-16 MPG with 80% HW / 20% city.

I changed plugs/coils/cleaned MAF sensor/Cleaner Air filter. Ill let you all know how much MPG i get next week.

 

There is no magic secret unlock code.

All rx8 achieve same mpg in same circumstances in same driving conditions.

This means that when someone swaps their "magical 29 mpg rx8" in Utah with someone else's "magical 11 mpg rx8" in California, both drivers end up getting exactly the same mpg as before.

Only public embarassment will result with contrary claims.

There is not much potential in the mpg arena we are talking pennies on the dollar. Better look at your $120 weekly grocery bill instead of your $30 weekly gasoline bill. Seriously.