I'm 300 miles away from home, away on a road-trip, with my M6 2004 RX-8. She has 16,000 miles on her.

All was going great. There was an S2000 on the highway, and we played around, gave it a good race to 126mph - and then my CEL started blinking. I used that as my sign that I had enough fun, and we just cruised together a bit from then on.

Later on down the trip, I have to accelerate to get infront of someone - the road was changing from 2 lane to 1, and the guy was blocking me.

I downshifted to third, gave it all out, she acclerated to 6500rpms, and would not rev past that. I had no acceleration - it was as if I had hit the rpm-limited fuel-cutoff of a car. The CEL blinked a few times, I managed to get infront of him, and continued.

This time, a bit more concerned with my vehicle, and wanting to get there in one piece - so I kept everything to normal driving, going only minorly over the speed limit.

So... whats wrong guys? What would cause this? The weather was 45 farenheight, clear early-day, as close to zero humidity as it can possibly get. Half tank of premium gas remaining, filled up completely at the same gas-station I always do around town. All windows/moonroof up and closed for optimum drag/fuel economy.

My car is 100% stock, and its to prevent problems like this that I've kept it 100% stock.

Any ideas? Anything I should check before I begin my car ride home tomorrow?

 

I've read other posts about this and when they had similar experiences I believe it was a misfire.

Whens the last time you changed your spark plugs? How many miles are on your car?

 

I, I omitted that one detail.

She has 16,000 miles on her - and she has the factory stock spark plugs. I havent worried about the plugs, simply because, every other car I've had has lasted 50k+ fine with their plugs.

 

Try taking it to a shop that will give you a free error code check - usually pep boys or auto zone will do it for free. That should tell you right away.

Since you have a 2004, you should go in for the Engine Cranks - No Start TSB. Free upgraded plugs, battery, starter, and flash of the computer. Might help the issue if the CEL codes report a misfire - and hey, it's free!

 

I'll do that, so long as I make it home in one piece!

Thanks dude.

 

Why not take it to a Mazda dealer and have them pull the codes. That way they can do the repair right there.

 

I think he was saying that I could go to any of those places while I'm away from home, just to see if it was serious...

And when I'm back home I can go to the dealership.

Thats how I read it

 

You can take it to any mazda dealer for warranty work, even when you're on the road. You might have to stay the night, though.

Mike

 

Agree regarding finding a dealer where your at, if at all possible. Check around this site and you will also find lots of thread commentary about spark plug life and replacement cycles that are a lot less than 50K with the RX-8.

 

they will all do that when help at high rpm for extended periods

you don't need a dealer just yet, it's detecting random misfires but not enough to fully engage a permanent CEL, they set it up that way intentionally, your car is fine for normal driving

 

Check your coils too. I had similar symptons.

-Jim

 

Check your cat. I have heard that when its clogged up the engine has problems going over 6.5k rpm.

 

Check for a mouse in your airbox...seriously. My car is experiencing the same issue; at 6,000-6,500 rpms, it falls flat on it's face and you have to shift to keep driving. I had a mouse in my airbox that shredded the airfilter and deposited stuff like birdseed, newspaper shreds, pieces of cloth. The dealer cleaned all that out, replaced the airfilter, did an injector cleaning, still the same problem. Prior to discovering the mouse issue, the dealer thought it was misfiring, so they replaced the plugs under warranty. Thanks to replies to my original post, I asked the dealer to eliminate the CAT issue and check to see if it is clogged. They did a test and determined it's fine. The latest chapter is the Mazda tech hotline told my dealer to warranty the coil pack. I am waiting to get the car back and see if it's back to normal. BTW, mine is a stock 04 base model 6 speed with 19,000 miles. Prior to this issue, it has run flawlessly.