I had bought a 04 rx8 a couple of months ago, it currently has 65k kms on it and it is a automatic transmission. I get horrible mpg, with a full tank i only recieve 300 kms. which is around 12mpg if im correct.

On start up it takes about 4-5 seconds for it to start now.

when high reving the engine light flashes untill i slow down. after checking the codes it stated it was an engine missfire.

im 17 and wanted to know the best possible way on how to make this car run as best as it can.

 

There's literally thousands of threads about this...

Check your CAT, change your spark plugs, wires, coils and get a compression test.

 

I get 12mpg on a daily ******* basis with perfect compression.

You blew your engine.

 

I blew my engine? Hopefully ur kidding

 

Well of course I would get new coils/plugs, an upgraded starter, seafoam.

Once that is done let us know... Ive been through the whole thing before.

 

Well of course you would, which is why he should be ignoring you and the rest of the shooting from the hip parts swappers. Seafoam is a waste of time and effort for anything other than occasionally running it through the fuel system for general maintenance. While the upgraded starter is nice, you really don't need to spend the money for it until the original starter dies. Unless the engine compression is really shot, with a good battery and the rest of the system functioning properly the original starter will start the car just fine.

The issue is likely in the ignition system. Probably at least one bad ignition coil, but spark plugs and the spark plug wires can also be a possibility. There are several alternatives. For the DIY approach you can either upgrade to the BHR ignition for $500 (just coils and wires, no plugs) or if you want to just troubleshoot what you have then see my DIY thread on GM/LS2 coils which also applies to the OE system.

Otherwise you can take it to a dealer or independent shop and be at their mercy.

 

I really wish this was a sticky
https://www.rx8club.com/series-i-tech-garage-22/suffering-misfire-start-here-222280/

 

search

 

Wow Team! You must have been having a good day, I haven't seen you extend a hand like this in a while.

 

It's all part of Team's initiative of becoming a less blunt poster lol

 

Well, the answer to that question is for you to take some time, do some research on this forum, and read through the various threads that outline how to troubleshoot the problems your car is displaying.

If it were my car, I would have researched the forum, then decided to inspect the spark plugs and spark plug wires, if not fully change them since the car is new to me and not running right. After my research on the forum, I would have learned that the ignition coils frequently go bad after only 30k miles, and would have ordered a whole new set of coils from a source like Advance Auto Parts, using one of the coupon codes to decrease the price of the coils.

I would also have done an oil change on the engine, the transmission, and the rear differential. Since the car is near the end of its engine warranty, I would have called Mazda to see if the car is still eligible for free engine replacement, and if not, I wouldn't have even bought the car.

There are many things you should have been able to learn on your own.
I learned all of this within the first couple of days after buying my car, and I didn't even buy a used car. I bought a brand new 2011 Sport. That was back in March, too.

BC.

 

Newbies...lol