This seems to be a common thread-type (losing power), but I'm starting my thread here because my issue only manifests itself under very specific circumstances, and nowhere else.

I was at the track this weekend. Specifically, I was at Texas World Speedway (track diagram here: http://img519.imageshack.us/img519/3465/tws29road.jpg), running in the anti-clockwise direction. Turn 10 is a slow carousel corner to the right, followed immediately by Turn 11, a sharp left-hander leading onto a straight. If you handle these two corners on-line, you have a quick weight shift from the left to right, coupled with some hard sideways G (again, to the right) as you accelerate past the apex at 11. This whole linked corner is done in third gear.

Intermittently, after apexing at Turn 11 (and putting the hammer down for the 11-12 straight), I'd lose power at about 6000 rpm. Once, it was flickering the Check Engine Light, and the last time, the CEL came on and stayed on. It's still on now.

This fault only happened at turn 11, and nowhere else. There are a number of left-handers at TWS (turns 2, 6, 7, 8, 12, and the 13/14/15 chicane), but it would only happen at 11. I would also think that the 14/15 part of the chicane should also cause this problem, since there's a similar quick weight transfer from left-to-right, coupled with another major acceleration point as you lead onto the main straight; the only reason I think 14/15 isn't causing a similar issue is the track-out point is further out, so you don't have to put as much sideways G into the car.

We ran the car through a fault code reader, and it came up with P0302, indicating a rear rotor misfire. Advice on this and/or other forums has come up with a laundry list of potential faults. To summarize them:

• spark plugs
• coils
• wires
• fuel pump
• catalytic converter
• just a quirk of the RX-8 / rotary

The first three seem a fairly obvious place to begin, as the car's right at 69,000 miles, and I don't know when/if they've been replaced by a previous owner (I got the car at 55k). The main reason I'm posting this thread is because of the extreme specificity of the problem, in that it would only manifest under certain conditions and nowhere else.

Any advice is appreciated.

 

Coils Fuel pump
There's a nice write up made by MazdaManiac, check it out.
It may be possible that you had misfires just because you stressed your coils, the loss of power\fuel cut-off is usually fuel pump related.

What's your mileage?

 

Last fill-up at lunch yesterday was 69,480. I put on maybe another 35 miles at the track (I pulled off after 10 laps or so, that was when the CEL went off and stayed on). After the track, another 100 miles or so getting back to Houston and then driving to work this morning, so I'm going to guess it's now at 69,610 or so.

 

It could very well be the pump then
Nothing major, left sweepers with cooked up pumps are not a good combo.

I would get a coil upgrade and keep the old ones for warranty purposes and a new fuel pump