Ka_RX-8

hi, i am new to here ,i just bought RX-8 2 weeks ago..04 GT 52K on!~manual!~BLK

so...i am only getting 10MPG, i know i shouldn't be expect a high MPG, but 10 is too low isn't it?is there anything i need to do to make it 16? that's good enough
(By the way all i did was city driving), i used SHELL V-POWER , i know the dealer who sold the car to me uses valvoline? oil...should i use another brand?
what is the rpm you guys change gear at to have a better MPG? should i change intake?exhuast? i saw something like cleanning the MAF sensor? how do i do that? is it hard? anyone can help me?? i am really concern about the 10MPG...=..=...i don't really want to go anywhere with the car..i usually change gear at 4000 rpm, and i know i have to red line it a couple time a week at least...

please help me out i really like driving it!! really really fun!!
apperciate it..!~

Charles R. Hill

iTrader: (7)

Can you itemize the questions abit so we can help you one question at a time?

REsuperD

i guess the main question was mpg. i think 10 is maybe a bit abnormal. you may want to change plugs/coils. mixed driving style (shifting @ 3k mixed w/ occasional redline) in the city usually gets me ~15k. you bought it from a dealer? if it was recently, maybe take it back and complain that this is totally abnormal and try to get them to give you new plugs

Ka_RX-8

sorry~

hi, i am new to here ,i just bought RX-8 2 weeks ago..04 GT 52K on!~manual!~BLK

so...i am only getting 10MPG, i know i shouldn't be expect a high MPG, but 10 is too low isn't it?

is there anything i need to do to make it 16? that's good enough
(By the way all i did was city driving), i used SHELL V-POWER ,

i know the dealer who sold the car to me uses valvoline? oil...should i use another brand?


what is the rpm you guys change gear at to have a better MPG?

should i change intake?exhuast?

i saw something like cleanning the MAF sensor? how do i do that? is it hard?

anyone can help me?? i am really concern about the 10MPG...=..=...i don't really want to go anywhere with the car..i usually change gear at 4000 rpm, and i know i have to red line it a couple time a week at least...

please help me out i really like driving it!! really really fun!!
apperciate it..!~

Ka_RX-8

actually the car got a new plug i guess 2k miles ago, the previous owner did it at mazda dealer

but it was maybe half year ago or something like that...um..

how should i complain about it? i mean we sign the thing was saying that they don't own me anything neither do i ...

and plus actually brake pad need to change soon...i hear some squeek sound..

um..can i make them do that for me also? i got a year warranty covered for anything happen to the car, mechanically....

lshu

wow so many questions... well i'll try to answer all of them:

mpg - not trying to make you sound dumb, but how do you calculate your mpg? people have made the mistake of dividing the miles by the capacity of the gas tank (16 gallons), instead of how much they filled up.

Your ignition coils can be worn, mine were at 50K miles and I was losing some power and mpg. You can change at low rpms (3-4K) and drive under 70 mph to save mpg, but you really should have fun and redline it at least once in a while, since carbon build-up in the engine is the most common issue with our engines.

Cleaning the MAF sensor can help make your car run a bit better if it hasn't been cleaned in a while. It's easy, open your hood and find the MAF on the intake tube, follow this DIY:
https://www.rx8club.com/series-i-do-yourself-forum-73/diy-how-clean-maf-94872/

Using any gas brand is fine, although I like to use top tier only (Chevron, Shell, or 76) for better detergent additives. Make sure to use 91 or 89 octane, especially in hotter climates.

You can use pretty much any oil, just make sure that it is at least 5w-30 weight. There is still controversy over whether synthetic oil can be used, but in my experience it has been good. For conventional oil I used Castrol GTX, and synthetic I use Royal Purple. I hope you know that the engine burns some oil by design, so check on the oil level every once in a while and top off if necessary.

Just because your brakes are squeaking doesn't mean the brake pads are bad, unless they are squealing 100% of the time! There could be just brake dust between the pads and rotor, or the previous owner could have changed the pads to higher-performance ones (which are squeakier). I'm sure you could make the dealership check it out if it seems bad to you.

Changing your intake or cat-back exhaust will not give you much more power (~5 whp) since the stock ones are well-designed from the factory. Change them only for the sound. Replacing your catalytic convertor with a midpipe will give you ~8whp however.

I have a feeling the search gods will be displeased. I just saved this guy like 100 hours of searching, haha

Ka_RX-8

WOW~~ISHU,thank you so much, yea ~~i didn't do that dumb way of calculating..haha..thanks for reminding tho...

oh..the ignition coils? okay i should just go to the dealer have them check whatever i think is wrong for me anyways cause i have 1 year warranty of everything inside the car...

yeah i've been looking at this forum for 1 month before i got the RX-8, i was really worry about the enigine flood and starter? it sounded really bad, but it've been fine for me i 've been following what people say here...

yea..once again thank you so much everyone...i got most of my questions answered , and actually i try to change shift at 3k now seems like saving gas a lot more

oh one more question , i know we have to warm up the car before driving it?

how long is a good warm up time? cause the manual said avoid long warm up time
i usually do it for about 3-4 mins til the idle goes little bit below 1K...

how long do u guys do it if u are doing it?

lshu

I usually let it warm up until the revs fall below 1.5K (usually within a minute or so), then drive off slowly, keeping revs under 4K until the temp gauge reaches the middle. That way you warm up the transmission at the same time.

RenKat

If you want to stop the floods, replace the battery with a good one and replace the starter with the updated new one.

ndhoffma

also, be sure to check the amount of pad left before replacing them... they may not be worn, just squeaky.

If you do need new ones, there are some good threads on different pads. (check the sticky in the wheels tires and brakes section)

04RX8man

check your air filter...mine was nasty and just by changing that i was getting 2mpg better....maybe it's time for coils....CAT maybe?