Serious Problem, hard to identify
 

Ok... From what I'm understanding, I'm suffering from a spontaneous fuel cut.

It happenned to me twice today, once in first and once in second... when revving high... as in flooring out the gear, it will sometimes lose power in second above 7000 rpm... seeming to go into a temporary limp mode of some sort.

well today it got worse, i tried to get the problem to duplicate in second and instead of losing power, it CUT abruptly like i took my foot off the pedal... And the car actually lurched forward with the torque... later it did the same thing in first... I've posted several threads about this in the past... and I've been doing some R&D and I think the fuel pump needs replacing but i dont know. after i turn off the car the problem goes away... its so hard to get it to duplicate, that I dont think i could get it done on warranty.

I dont know guys... is this an over-active nanny system? or am I looking at alot of cash?

Well is your DSC on or off?

If it's on I suspect your DSC is stepping in and cutting the throttle when you start spinning the tires. like it's supposed to.

If it's off then I suspect your coils may need to be replaced and you're getting some bad misfiring.

Other option is clogged fuel filter sock.

it needs to be hooked up to a scanner and the freeze frame data looked at. i bet there a stored code.

My friend had the same issue. When in 1st gear he seen some cars coming, tryed to wot and his car was very slow then went really fast, he was like shit! lol
He took it to the dealer he had a ton of misfire cods. He also was charged $500.00 for new coils spark plugs and spark plug wires.
As for your fuel cut issue, have a look at SteathTL DIY fuel plump change where you can look at or clean up your fuel sock.
Check this out; https://www.rx8club.com/series-i-do-yourself-forum-73/diy-clean-tank-sock-filter-164287/

would a dirty fuel filter make it seem sort of like flooding on startup? maybe some hesitation as well?

Sell me your front lip lol

sorry,

year mileage, tranny..

was the car warm? how long were you driving it? outside temp?

beers :beer:

you wish.

:rofl:

Pull the codes and make sure you didn't get any miss-fires that you may have missed because you were driving and didn't see the flashing CEL....

I'd say if there are no misses, than the problem would be fuel and I'd clean your fuel sock and then perhaps start looking for a new fuel pump.

Does it do this all the time, or only when you've been running the car for awhile?

yeah without a year and mileage its hard to tell

one other obscure thing it could be is a dirty MAF, when they are dirty they retain heat more so the ECU doesnt have to throw as much voltage to them and it freaks out the ECU. This makes the ecu see the element retaining a higher temp as in less air going by than there should be. and to prevent a rich run it leans it out till eventually it cut. does this in milliseconds if thats the case.
my old mazdaspeed did this. I broke 3 motor mounts before figuring it out

COILS, same thing happened to me last week.

wouldn't coils throw a misfire code though? When my plugs were bad, this is what happened to me...

I'm thinking that without a misfire, that indicates that ignition is not the problem, but it is fuel... but with a misfire code... all of this changes.

But then again, I have new OEM coils waiting for the stockers to fail. . . I've had these coils for 30k+ miles (since I bought the car) and they're over a year old.

Coils don't throw a code. A misfire throws the code.

might be a noob question - but wouldn't a bad coil lead to the spark plug not firing and thus a misfire?

^Yup. Thats why some mazda dealers will do the coils and plugs.
Anyway,
Thats really odd cuz I just changed my coils spark plugs and spark plug wires.
Plus my friend AJ just had the same issue. He changed his plugs. There where only on his 8 for about 6 months and now his car feels great! so his issue was just bad plugs.

would this problem be covered under warranty?? im not sure cuz its coils?

Dont know. Its all maintenance.