Thedude24

I, like many others, experience this same problem where after a long drive my car will stall out at idle. However my way around it has been to downshift back down to 1st gear if you can and give it a bit of gas for 15 - 20 feet and then slow down to idle. Of course its not the best fix especially if you have to come to a sudden stop but its been a reliable way for me. I also never see any one mention it but this only happens to me if I drive in 3rd maybe 4th gear for a good amount of time. I can drive/ have driven in 2nd gear for a crazy long time and have not stalled out.
for those interested I drive an 05 AT RX8 which I'm coming up on my 1 year anniversary :D
One thing I want to try is cleaning out the Throttle body and checking the E-shaft sensor.
I know the front rotor of the engine has low compression but I want to rule that out because when i do stall out my car will start up like a cold start, but I am also still behind on the learning curve of my car.

Loki

iTrader: (1)

What intake do you have? Is everything original?

Thedude24

When I first encountered the issue yes, I have had some things replaced since then like the SSV and the other solenoid back there, also had a new radiator installed. The intake body had been cleaned out as well. I clean the MAF sensor every so often. I've installed a cold air intake which of course didnt help the issue. The only other thing I've done is install a HKS hipower exhaust, which again was just added for fun. The whole stalling thing isn't an issue Im super pressed about since it's rare for me to need to go on the highway for whatever reason, but over the past year I will randomly stumble upon posts about it but never have I seen anyone mention the info I have in my post
I forgot to add I have changed my PCV i guess because it has smoothed out my idle could have something to do with it but I wouldn't know for sure since the only reason I changed it was because the CEL came on but it's possible it could have been failing for a while because the cars idle was on the rougher side ever since i bought it.

Loki

iTrader: (1)

What code is the CEL for?
There isn't really a separate PCV, so what did you change?

Rough idle and stalling when warm, with good hot restart sound like a vacuum leak to me. What are your fuel trims on a warm idle? It's also possible you've fixed the original issue, but created another similar one with the changes you've done. What intake is on there now?

Thedude24

My b I meant the purge valve solenoid the code was a P0443 and that did fix my rough idle as for the stalling I dont know if that did because I havent had the need to drive my car for extended periods of time past 2nd gear. And just to reiterate its not just stalling when warm its stalling when warm after being driven on 3rd gear for a while, I can drive on 2nd gear for just as long or even longer and not have any issues.

I dont know about the fuel trims I'll check that tomorrow

I guess i also oughta find a way to check for vacuum leaks too.

My intake is the AFE takeda stage 2 intake

The SSV and other solenoid + radiator was done at a Mazda shop (summer 2021
The intake was done a couple weeks after that by a friend and myself (fall 2021)
I did the PV solenoid about two weeks ago
and I just did the exhaust last week with my uncle

Loki

iTrader: (1)

The fuel trims are how you tell if you have a fuel leak. They should be near 0.

As far as the intake... most intakes on these cars are worse than stock. They mess with the MAF reading, in addition to performing worse in power production. You might change back to stock to see if that fixes it.

Thedude24

Put back stock intake didnt change anything.

I'll check the fuel trims sometime soon tho

I wonder though if anyone else has had the same thing where if they downshifted before the stop and didnt stall out verses stopping in a gear higher than second and stalling.
I've always wondered if the problem could lie in the transmission itself.

Loki

iTrader: (1)

The torque converter should let the engine continue spinning even if the trans isn't moving, so I'd be surprised if it were that. It's possible a shift solenoid is on its way out and it can't properly manage a decel downshift... but that's an easily detectable condition that would give you a code?

Thedude24

Oh ok thats good to know and yeah my car isnt showing any codes

So for now I'll try and knock out the other stuff and just keep troubleshooting I guess, thanks for the replies