RX8 ~18k miles on engine. After the car warms up, say 15-20 minutes the engie stutters/hesitates when a go to WOT. For example I put the car in 2nd gear and go to WOT at 3500 RPMS, RPMS climb and then stutter at ~6,500RPMS and then the engine cuts out and drops the engine down, I move forward against my seat belt at the sudden slow down. No CEL (Check Engine Light) ever comes on during all of this.

BUT

If I am in 2nd Gear at 3500 rpms and slowly increase the RPMs, I can push the RPMs up to redline with out any problems, but I increasing hte RPMS at a rate of ~250 RPMS per 2 seconds or so.

Also

If the car is not underload I can Rev the engine to redline and the engine does not choke out either.

So basically the engine stutters and hesitates when warmed up and under WOT, in the higher RPM bands.

So any thoughts what it could be? I do no think it is an engine internal mechanical issue because I can hit high RPMS with the slow RPM rate of increase or quickly with revving.....and the car idles fine.

The car goes into the dealer on the 27th for this and for the Thermal damage recall.

 

which flash do you have?

 

Good questions...I have the N Flash

 

Oo.. I had the same exact thing happen on my 8.. Except I believe it was WOT in 3rd, not 2nd. Foot to the floor, and all of the sudden the car is coasting not accelerating, and after a half second it "remembered" wtf it was supposed to be doing. It was lovely.

 

Could be Plugs or coil induced misfire, also how much fuel is in the car?

 

A little side question. You say you're bringing it in on the 27th for the thermal damage recall also. Did you already officially receive the recall notice from Mazda to bring it in? Or did you just request to have it done early.

 

This will happen in any gear, but normally I only go WOT in 2nd or 3d gear and still have enough road left...did you get this issue resolved on your 8?

 

It was on the highway...have ~ 3/8ths of a tank of fuel

 

I called the Service Dept and they said....what Recal. So I started reading them the July 8th letter from MNAO VP of Sales and Field Ops. Service dept said he was aware of that but had not received any directions as to the fix. I hope they have the solution given to the dealers before the 27th. :-)

 

My car had a similar hestation/loss of power.. right around the same milage point. The cat decided to fail, blocking the exhaust (somewhat) causing the loss of power..

New cat, felt like a new car.

 

My guess is that it might be the system pulling the timing due to too high of a knock count from the detonation sensor.

What kind of gas are you running?
Could you have heavy carbon build-up? This can cause pre-ingnition as well.

Chris...

 

Would I not get a CEL with engine knocking?

 

You would get a CEL if there was a misfire, not just for regular knocking. I would also expect a CEL if there was a problem with the cats too.. 02 sensors get cranky with blocked up cats.

I haven't taken my car to the shop for it, since the problem has only happened a couple times. Especially when I've brought the car in previously for a fuel pump that was squealing like a stuck pig and they "couldnt find anything wrong.." I wouldn't expect that they'd be able to sort this out either.

I'm taking a "head in sand" approach at this point.. I'll keep puttin in 93-94 octane fuel and driving normally, and if the motor takes a colossal dump on me, well.. thats what warranties are for. Maybe I'll end up with a motor that gets over 13mpg next time

 

I didn't get a CEL until a few weeks after the problem started.. by the time I did get a CEL, I was getting 16 MPG (freeway) on a good day..

 

I drove home yesyerday from work and had the same issue, but after sitting in traffic the RPMS started cutting out sooner in 2nd gear around the 4,800 RPMS. It seems the longer I sit/crawl in traffic, the lower the RPMS will become when the stuttering will start at WOT..

 

Jaguar_MBA, that sounds exactly like what happened on mine... (only my CEL came on when I did the WOT).

 

compression loss and probably coolant leak from overheating i bet. you should get it in

 

this has happened to me before and i found out that it was my master cylinder brace which was on too tight, and after i loosened it, it was fine.

but if u dont have a master cylinder brace, then i dont know sry

 

cat was getting clogged with the stuff thats inside that proby is breaking apart and clogging up and restricing air flow..

I had my cat replaced tech took my cat out and it fell apart and **** was clogging the rest of the cat...

There was a TBS out on replacing the cat

 

Took back way home from work, less stop and go traffic. after driving for ~ 30 minutes at ~60MPH, the car started to bog down again at 7,200 RPMs in 2nd gear. No CEL.

 

Also I had a brand new tank of gas with 93 octane from Mobil so bad gas can't be the issue, this last time.

 

Car was brought to the dealer yesterday, the Tech could not recreate the issue so I drove the car over my lunch brake for ~45 minutes until the hesitation started, then drove the Tech. The Tech (very knowledgable Senior Tech) agrees that something is off...hopefully tomorrow or tonight thet can tell me what is wrong. I did get a flashing CEL today for the 1st time. By the way, they gave me a Mustang rental car :-)

 

My dealer still has my RX-8, they could not find anything wrong with the car when the poked around and looked into the ECU's memory. Cat is good. They had to call the Mazda Hot line for guidance. They decided to replace my coil packs on Monday/Tuesday. If this does not work then they are going to order me a new engine.

 

Same problem heer. Engine stop at 33mph at 7500 rpm in 1st, 53 mph at 7250 rpm in 2nd, and 75 mph at 7500 rpm in 3rd. I'll be seeing the dealer tomorrow to get the cat looked at. No CEL, and I think that I got the R flash several weeks ago

 

jaguar did they actuall look inside the cat?