Stumbling through 2000-2300rpms
 

Things have been going well for a while, until yesterday. On the way home I noticed while going through gears it stumbles and struggles right around 2000rpm and for about 3-500 rpm after that. Most other ranges seem okay, I can hit red line, and it seems to pull correctly after the bog.

I have never touched the cat, I have had the car since 2010, it is an 05 with currently 110k miles, got mazda swapped engine at 70k.

I found this list which would point to maybe front O2 sensor, though it might be cat too. It really sucks because 1, it is January in Minnesota and I dont have a garage available to get under it, and 2, I just started working this week after a long retraining and layoff and literally have less than 200 bucks in the bank account. Any help on what to test and or solutions would be great, especially if you are in or around the Twin Cities Minnesota and have some space for a fellow RX8 dude to wrench :)


Engine Power Loss
• chokes as revs increase
o O2 sensor failure (too rich)
o MAF failure
o MAF disconnected
o e-shaft sensor fouled
o accessory belt fraying
• high end power loss (hard fuel cut)
o Rev limit reached
• high end power loss (jerky and stumbling)
o Ignition failure
o fuel pressure loss
o e-shaft sensor fouled
• high end power loss (smooth)
o Catalytic converter clog
o air filter clog
• low end power loss (smooth)
o Engine compression loss
• low end power loss (stumbles)
o Ignition failure
o front O2 sensor failure
• revs slowly but smoothly
o O2 sensor failure (too lean)
o catalytic converter clog
o air filter clog
• sudden power drop at a specific rpm
o Intake valving actuation problem
• trouble getting to redline
o Ignition failure
o front O2 sensor failure
o catalytic converter clog
o air filter clog
o e-shaft sensor fouled
o fuel pressure loss
o MAF failure

Have you tried cleaning your MAF and ESS?

Why are you driving at 2000rpm anyway? That's almost lugging the engine in most gears.

I have not. It seems like the MAF might be easy enough in this cold weather, but I do not really currently have access to a heated garage so any involved repair or troubleshooting might have to wait a little.

I will start there for sure though, thanks!

Oh you know, from like every stop light and trying to keep tracking in icy and snowy conditions. But f*ck me right?

Let me rephrase: if you're shifting up such that it lands at 2000 that's probably too low in any gear beyond 2. These engines have no pickup that low.

Additionally, if you are spinning, especially up a hill, and your traction control is kicking in, it will cut power until you hook up. See if it behaves the same with traction control off.

I'm not trying to disparage you, but as you say money is tight, free fixes first.

I have turned traction off and it doesn't change the behavior. It seems a little better in warmer weather (though it hasn't been warmer than 20 since the symptom started)

I've had the car for nearly a decade, and have never experienced this issue regardless of shift points. Especially in stop and go traffic, I find myself in this RPM range on fairly regular occasion. Sorry that I took your original comment as sarcastic, but it also didn't help address the issue whatsoever.

No CELs?
A bit of good news is you would normally get a CEL with a bad cat.
Ok, free fixes without getting under the car;

Get it scanned for free at most parts stores.
While you're there pick up some MAF cleaner.
That's not free, but about $6 iIrc.
Clean your MAF sensor, you may be able to see your ESS from up top if you take the air cleaner box out (PITA), and try to spray it with your MAF cleaner, couldn't hurt.
Check your air filter and intake for oil, that could give you problems.
Be sure your battery terminals are clean and tight, then when you're done with that reset the NVRAM with the 20 brake pedal stomp.
That's all I got, except maybe check for vacuum leaks if you have a little propane torch handy.