i recently bought a 93 mazda mx3 with a 24 valve DOHC 2.4 lt v6 in it. She sat for a little bit and the guy had to sell it. I put seafoam in her to stabilize the gas and she ran better for a while. On occasion she would stall when you took a corner but it would take a few tries and she would start back up. After a 45 min drive from where i use to live she started bucking back and stalling out no matter how much i put my foot on a pedal she wouldnt go over 20 mph and she only does this when she gets to running temperature. she has a really bad fuel smell even when parked, ****ty gas mileage, and black smoke out the pipe. The check engine light stays on for a while then eventually goes out. I recently replaced the throttle position sensor and it helped some but the problem is still there. I know shes in need of 2 oxygen sensors a right side radiator fan, and a damn good tune up once she stops stalling! numerous people have told me it could be the mass airflow,egr, and a clogged catalytic converter. She has no knocks, ticks, or anything in the engine and she shifts beautifully with a rebuilt transmission. If anyone has any other ideas what could be the cause of her stalling please let me know =)

 

Based on the symptoms, I'd say catalytic converter is a strong possibility. That's what happened to my Dakota when it's converter clogged, was on a long trip, and barely made it home. Even with pedal to the floor, it wouldn't go any faster than 25.
I recently had to let my mx6 go (same 2.5 v6 you have), so I got everything off the car, including the exhaust. It was stalling out frequently, and I couldn't figure out why. When I cut the catalytic converter out, it was partially melted. I can't say that was the only factor, but was a definite contributor.
I hate catalytic converters: that was the cause of the death of my first car
The mass airflow sensor and egr can be tested on the car, but I don't know if they'd cause the same problems.

 

Take out the O2s and see if it runs better with a bit more free exhaust, did that on a Dakota I was working on once as well, ran great once I took out the sensors and it could breathe a bit through the holes.

 

Thanks guys, I have a good friend who knows quite a bit more about mazda's than i do thats helping me check it out. The poor little girl never got her maintenance that she needed. the guy just ripped her around. Im glad i got her when i did. We also think the fuel injectors are bad, so i just going to replace them. Ive been saving up every damn penny i have and working doubles just to put money into her, but on the other hand ive got my daily driver that needs some serious front end work...rack and pinion, struts, shocks ect...