I bought my 04 rx8 in february 2005. I have never gotten better then 13 mpg combined city/highway. Driving style doesnt seem to affect mileage whatsoever......nomatter if i drive like a granny or like I just stole it. ive tried all different grades of gas.
I live in los angeles and I ussually am not involved in too much traffic, and I am on the freeway 50% of the time. Most people posting here complain about 16-17 mpg! what a joke!
But mileage isnt even my biggest problem. The car has soo many rattles that I am getting depressed. I pay soo much too own this car and I feel like a bum ridding in a 72 PINTO sometimes. any sharp bump results in a harsh thumping sound coming from what seems to be the center of the dash. This terrible low quality sound is accompanied by various rattles throughout the dash and around the drivers side.

I drove a honda civic the other day and it seemed like a 2005 lexus ls430 in comparison. I fixed the speedometer cluster (a common problem) from rattling by placing some quarters in the gap.
I also notced more rattles coming from the glove box because it wasnt tight enough. I also had a problem with squeeking brakes that the dealership finally fixed. My car goes threw 1.5 quarts of oil every 1k miles.
I want to sue mazda...this is not right. I went to the dealership a couple times to complain about this stuff....they always say that "well the car shouldnt be burning more gas then usual" and "we dont hear any rattles". What am I supposed to do?? I cannot live with the fact I m paying my *** off for a car that has no refienment and has more rattles then most 15 year old cars.
I am soo mad about the rattles I almost forget about the fact I am paying more then $300 for gas every month! what Am I supposed to do?? anyone?

 

You need to review the lemon law in your state more closely. Sell the car, problem solved.

 

Sounds like you are Reving it too much. Keep the RPM near 4,000 RPM.

Try shifiting into higher gear.

 

Is it a new car?

The 13 mpg and oil consumption are pretty "normal" for this car's break in period. Give it a few thousand miles or so and you should see improvements.

My car did the same thing, and I dont have rattles anymore in the speedometer cluster, i get 17-18 mpg in mostly city driving, and my oil is back to 1 quart per thousand. Of course, this is 13k miles later. But mine has been pretty even like this from about 3K, and it seems like gas mileage is getting better. I keep it below 4500 for 95% of this driving though.

 

sell the car get a prius, the sport package one.

 

As i said, I have tried different driving techniques, I kept it under 3500 rpm for a full tank and no improvment! the car has 6000 miles on it

 

hmm i wouldn't say you have a lemon....maybe a lime though

 

what flash do you have? was your car new when you got it..maybe they flooded it taking it off the boat and didn't replace teh sparkplugs. lots of lil things it could be....clean your MAF or get a new one....you could try that..i hear good things about doing that..helps with mpg...(at leat right away not sure about long term effects)

 

for your car to be a lemon, you would have to bring your car in to get all of your problems fixed THREE TIMES before you can apply for the Lemon Law. Just because it has rattles and you do nothing about it doesn't mean you have any justification...yet.

and your claim of adding 1.5 quarts of oil evey 1000 miles isn't unheard of, especially if you rev the engine. sorry, but you have no grounds to sue Mazda there...

how about you just sell your car and get something else. forget about lemon laws and lawsuits.

 

hehe here here all hail Muagtu the voice of reason..muahahahhaa

if a civic felt like a lexus..get a civic...either that or lexus went to sh!&

every car is going to have some squeks and rattles..you fixed one of them...so why not fix the others on your own? it took my dealership 6 months to fix one of my rattles...but that was the only one i could do myself.....it was the rear window the seal was bad on one side...not enough to make it leak but enough to make it shift and rattle...very annouying...but they fixed it. eventually :D

 

Thats not true.

My car got 17.5 mpg the first half dozen tanks.

When your car is fully broken in, you might seem some slight improvement, but he's not going to see 13 mpg jump up to 18.

 

this car's gas mileage is more dependent on how much you ARENT moving,... stoip an d go driving (even on the highway) destroys the mileage, take a full tank road trip and you should be getting int he 20's.

 

The more time you spend letting the engine idle, the more fuel you'll consume.

 

I too get between 13-15 mpg. High revs/low revs, seriously makes NO difference. I do mainly city driving and agree that things get even worse when sitting in traffic a lot. The furthest I've ever gone on a full tank is 344 Kms (214 miles) and that was with a couple of short trips on the highway. I avg around 300 kms per tank (which usually includes driving with the fuel light on for a while!). I love the car, though, and have just accepted the poor mileage.

 

I am on the n flash. The car had 30 miles when i bought it. Dont get me wrong here people...this is a fabulous car...when the radio is turned up and I am speeding threw the canyons I feel like a million bucs, And my driveway would look soo bland without it. I am mainly just mad that soo many of you have tighter, better mileage cars. Luck of the draw as they say, I will end up spending more then a thousand dollars more a year then most rx8 owners on gas. I cant trade the car in because I would lose much more then the extra cost of the gas that the rx8 consumes. I was thinking of getting a canzoomer, but i know this only helps mileage in the upper rev range, I f I am getting the same mileage while shifting like a grandmother, then obviously mileage will be the same. I guess The only reasonable thing to do would be to work harder and make more money so I dont have to sweat this kinda crap anymore.

 

you said that you have about 50% highway driving...what speed do you typically drive at? if its over 3750rpm (73mph) in 6th, then your secondary ports are open, which consumes more gas. and if you are over 4200rpm, supposedly the fuel mappings change to a slightly richer mixture, which consumes more fuel. not to mention that the faster you drive, the more wind resistance you have to overcome, which means more fuel used.

also, how long do you typically wait after cranking the car before you start driving? some people on here wait as much as 5-10 minutes before driving off. that's a sure fire way to kill your fuel economy.

so basically, keep it under 70 and avoid long startups if you want to improve your fuel economy.

 

I have less than 2000mi om my car and I just checked my milage and I'm just under 18 mpg on a mostly city driving. It was much lower before when I first bought the car though. I shift aroung 5k rpm and redline once a day. Previous post suggested cleaning your MAF as well as changing spark plugs, these might work. You can also reset your computer after you made the changes.

 

The lemon law only applies to drivability of the car. Rattles do not count. I guess this does vary by state so you'd have to check your state.

We are looking into the lemon law for my car for the power loss issue. We'll be taking it in next week for the 2nd time for the same problem and things are only getting worse... I almost got beat by a ford ranger yesterday! I got no oompf after 5k rpms.

Good luck! I had a rattle and was bummed until I reailzed it was my garage door opener! =)

 

The high oil consumption and low gas mileage are typical of new RX8's. Both are flaws of any rotary engine even after the break-in period. Yes, the use of oil should go down and gas mileage go up (on any vehicle). That is just weird to me. You are the first person I have heard of with this type of problem. I read where you are very easy on the car so it may go beyond that. My guess is the electronics. You may need to take it to the dealer and have the ecu remapped or even replaced. I would take it to a "trusted" mechanic first and let them take a good look at it, drive it, etc. But the guys are right about the lemon laws. Plus dealers tend to be a**holes b/c "there can't be anything wrong, it's just you". If that doesn't work, just take the loss and sell it.

 

I would bug the mazda guys unitl they fixed it or gave me a new car - remember this is supposed to be the "top of the range" MAZDA and any issues should be addressed and fixed to meet customer satisfaction.

 

Do you take a lot of short drives (15 minutes or less)? If so, then you should expect to get bad gas mileage. For example, I used to have a Honda Insight which got 55 - 60 MPG on the freeway. However, during short 15 minutes drives the mileage was only 42...quite a significant drop.

 

Also, try resetting the ECU.

 

I also get 13mpg. I've learned to live with it.