Can no longer maintain ~75mph while on a slight grade.
 

I have searched a bit on the forum for this problem and I wasn't able to find much, and I didn't see antyhing in the ~3 pages of threads in the "Issues & Problems" section of "The Tech Garage". I see some people reporting a complete loss of power accompanied by CELs, but I don't have either of these symptoms. Others who have complained about a loss of power were told that it's probably a cat or coil problem and would be fixed by the latest recall. Well, unfortunately, I've had all of the recalls performed (the latest one was a few months ago), and my engine/cat supposedly checked out okay.

I first noticed this issue a couple of weeks ago when I had the cruise control set at ~78 mph on the highway (6th gear). Whenever the car encounters the slightest of inclines, it starts losing speed. In some cases I must downshift to 4th gear to get enough torque to accelerate. The car was definitely not so underpowered in my first 3.5 years of ownership. I am not getting any indicator lights on the dash, nor do I hear any strange noises. When I exit the highway after ~20 minutes of cruising, I notice that the car seems very sluggish, i.e. WOT in 2nd gear seems to barely accelerate the vehicle. Yes, the cupholders and base of the shift lever are hot--but these areas always got hot during normal operation in my experience. When I start the car cold and drive to work on surface streets, this sluggishness isn't nearly as pronounced.

Does anyone have any ideas as to what could be happening? My best guess is that the cat is bad/clogged is restricting the exhaust when it gets hot; however, why would the dealer tell me just a few months ago that the cat is fine? Is it possible that it deteriorated so rapidly in just a few months? Any help would be appreciated.

Partially Clogged Cat. You likely have to push it a little hard for it to show right now, but it is somewhat clogged.

Chances are that the dealer did not pull the cat to visually inspect - they probably stated it is OK because you have not thrown any CEL's yet.

And if it's not coils, plugs or the cat. Have you checked the air filter in the 3 1/2 yrs you have had the car? A restriction on the intake is just as bad as the exhaust.

I hae the exact same problem with my 04. Car would decrease speed on slight incline around 70 mph. I could put the pedal to the metal and nothing happens. On regular roads, I could stomp the gas in 2nd gear and the car would slowly climb in speed. It was as if I was in 6th gear instead of 2nd. Took the car to the dealership and they had it for 5 days. When I picked the car up, they said they replaced the rear coils or something like that. I asked could it have been a clogged cat and the tech said my cat was ok.

Three days later, the problem came back with the loss of power plus a CEL. Will be taking the car back to the dealership today.

Oh and also, I've had all the recalls done.

That sucks man... I will be taking my car to the dealership tomorrow. My wife was driving the car yesterday, and the engine stalled out shortly after she exited from the highway. It took her several minutes to get it started back up, and when it finally did start there was a lack of power. I hope the dealership techs know what they're doing so I don't have to make multiple trips like you. I'm hopeful, because when I called and described the symptoms to the tech, he mentioned that it sounds like a clogged catalytic converter.

apex seals drying out.. recall not preformed properly.. or damage was done and is showing up now..

new motor time.. i have been through this..

beers :beer:

echo
 

^^^swoop said it, and if possible replace the cat with high flow or "test pipe"...I think a fundamental issue with the renesis is that side seals fail (as opposed to just apex) because of the extreme heat and stress of the exhaust being peripheral. In older rotaries the heat was concentrated on the rotor housing (as opposed to the side housing, rotor housing, and rotor)..on many old 13b dismantles you would see a bubbling of metal around coolant seals near exhaust ports...but on a peripheral port motor that heat is on the side seal constantly and the effects have to be more because the rotor's side seals are always touching this "hot spot"...the flaming begin, but entertain the thought (please) regardless of my newbie status...

wow,

you are way above the board.. you are the king of the newbs... :eyetwitch

no flaming, you have a clue.. and my guess is more than a clue... thank you..

beers :beer:

thanks, I take that in the highest regard...

nice to see new and have a huge clue..

welcome.

beers :beer:

Got the car back from the dealership. They replaced the rear plugs. Seems fine for now. We'll see whats next.

Am having the same problem here in MS, but it happeded a few times last year as well. Sometimes, there is viretually no power on the interstate, and you can floor it with very little difference. Idle is rough, and it has died a number of times. Have had all flashes and coil pack replaced, but plugs have almost 30k on them, so maybe it's time. I'm leaning towards the cat, but am taking it in tomorrow to see. Will keep you guys posted.

UPDATE: I got my car back from the dealership, and all they did was reset the "keep-alive memory". They said they couldn't duplicate the problem, but I noticed they only drove the car for ~10 miles, and it's at least a couple of miles to the freeway. I must say, though, that the car does seem somewhat better since I got it back. It still seems a bit sluggish to me, but not enough so that I could easily convince a technician that there is a problem. The idle also seems a bit smoother, so maybe that simple computer reset actually helped.

I have taken my car to mazda many times with the same issue. Cant go anywhere on the highway...car seems like its trying to accelerate but something is holding it back. They havent been able to offer any kind of fix for it and have told me everytime that the car is fine. Its beginning to piss me off. They told me to bring it back when something breaks. F that if i can get it taken care of before it happens. Had the plugs changed. Temp. Fix, issue came back, Had injectors cleaned. Temp. Fix, issue came back. Now the car seems to be drinking coolant though there is no signs of a leak and has power loss pretty frequently throughout the day whether on incline or not. idk what to do anymore. Serious hesitation that needs addressed asap. Any advice?

cat clogged, baked coolant side seal now burning coolant...motor time call MNA now! They will be happy to know the dealer caused them to drop 5g's on a motor swap that could have been taken care of with an $1100 cat...

UPDATE #2: The problem has not gone away--in fact, it seems to be getting worse, and today it was so severe that my car stalled while rolling up to a stop sign (after I had been on the highway for 20+ minutes)! I couldn't get it started for 10 minutes! It was quite embarrassing to have dozens of cars roll by me and stare at me while I helplessly tried to start it back up. After minutes of cranking it finally fired up, but the idle is extremely rough and it almost sounds like it is missing constantly. The same thing has happened to my wife twice in the past few months, and she refuses to take my car now.

I really don't know what to do. I feel like every dealer I've been to around here is clueless when it comes to servicing this car. Just like WisslesRX8, the techs told me that they couldn't duplicate the problem so there was nothing they could do. They also claimed that the cat was fine, although I have no idea what they did to actually test it. Next time I take it in I'm going to insist that they ride with me so I can show them the friggin' problem. It seems to me that they're just lazy and they know diagnosing and fixing the problem is going to be a big undertaking, so they're playing dumb...

PS: I recorded the exterior sound of my RX-8 to give you an idea of how awful it sounds when the lack of power is very noticeable and idle is extremely rough. Please take a listen to it and let me know what you think. Take note of the low-frequency impulsiveness associated with the firing events. That doesn't sound like normal combustion to me!

http://www.box.net/shared/lq6tgsg4ir

So, nobody has any thoughts after listening to that audio?

Doesn't sound like a cat problem. Sounds like it's in the engine itself. I've never heard a rotary sound like that.

2 years ago (@13k mi.), I was having a warm start problem and the exhaust seemed be louder than normal. After a couple of trips to the dealer, over a few days, they finally replaced the engine.

Continue pressing the dealer. A lot of dealers won't even "try" to diagnose your issue. That KAM reset is just stomping on your brakes a couple times and sending you out the door "hoping" your issue would go away.

Unfortunately, I know it's a huge inconvenience for you but keep going back until they start to do something about it. Yeah, I know it sucks..

Mine's been acting the same way, no stalling or rough idles. But the loss of power is definetely there. 5K in 2nd gear, then WOT, and it's as if I'm in 6th at 40mph. Very slow gradual climb. At this point I am nervous to race an 82 Civic :/

Tomorrow I'm going to put a dif exhaust sys on it replacing with high flow cat as well.

My car just feels out of tune or running too lean...

it is most likely the motor... try premixing and see if it helps. if it does then it is the motor..

beers :beer:

That sound was hidious. I'll bet by the sound your compression is way down. Make the deaker run the compression check. New engine time.

sounded like my car before the engine finally gave way, I got the engine replaced man

you probably pwned the car a bit hard or maybe you didn't do all of the services?

if not, then you probably got the 1 in 100 engines that finally died..........oh well, consider yourself unfortunately lucky, just like me

I ran into similar problems where my car was sluggish and had rough idle after driving long distances in high temps. Read this post, maybe it'll help you:

https://www.rx8club.com/rx-8-discussion-3/no-more-power-loss-124221/

no offense, but you said your wife drives your car too? It might be possible she was babying it and causing carbon to build up in the engine? Just a thought. Hope my post helps.