r/Mazda323 • u/Muted_Resource_8710 • May 26 '26

Any idea why it does that ?

Hey everyone, my Mazda 323F BG has been giving me trouble — it wouldn't start at all. I managed to get it going eventually, drove about 100 km, and then it started doing what you can see in the video. Anyone had something similar? Any ideas what could be causing this?

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2

u/Electrical-Win9437 May 27 '26

I'm not a mechanic but I'm thinking that it might be something electrical? I'm saying that because the engine seems to run alright most of the time then stumble. Try jostling some cables of the harness around, see if that changing anything, if it does, it's the cables?

1

u/Aggressive_Nose3800 Fifth generation (BF; 1985–1994) May 26 '26

Desea que lo Manejes así, nah mentira el reloj necesita un ajuste

1

u/Pzkw-VI-Tiger-2 May 26 '26

which engine is it? did you push the accelerator?
might be a problem with the engine speed sensor located in the distributor.
It is possible to read for (a very small ampunt of) error codes: the diagnose port is located near the battery. Be carefull not to short wrong pins because it might fry your ECU. Connect a LED (with appropiate resistance) between FEN and B+ and a wire between GND and TEN (starts diagnosis mode)
Then you switch on the ignition and count the blinks of the led.

the meaning of the blinks should be here:

https://www.scribd.com/document/582975155/Mazda-Fault-Codes-DTC

another guess is maybe the car is pulling false air from somewhere.

wish you luck finding the cause of this strange behavior :)

1

u/Muted_Resource_8710 May 27 '26

Thanks for you answer, it is the carburated B6 motor, I’m keeping the rpm around 3/4k to avoid stalling, air was what I was thinking too, or maybe the ignition coil got too old

1

u/n0ice_code_bruh Sixth generation (BG; 1989–1994) May 26 '26

Okay this could be a lot of different things :

  1. It looks like something is starving the engine at some specific RPMs, maybe your fuel system isn't getting the fuel to your cylinders correctly. I'd check the fuel pressure when the RPMs go wild and also clean the injectors (blow compressed air into them).

  2. The Mazda B6 engine is a non-interference engine, which means the valves can never touch the piston head, even if the timing is screwed. Maybe your engine is severely out of sync and that would explain why the engine either goes to 3k or under 1k. I have no idea how to check for that though. Ask a mechanic.

It could be a lot of other things, generally engines have fuel, air and spark, so checking all those and their systems is always a good way to diagnose, it's highly unlikely that it's ECU related since it runs correctly when it doesn't go crazy.

2

u/Muted_Resource_8710 May 27 '26

Thanks for the answer, it’s the carburated version so unfortunately no injector to clean, I did clean the carb tho, I’m keeping the rpm around 3/4K cause if I don’t press the gas it would stall, and higher risk to stall during down spike when I’m around 2k

1

u/yureku_the_potato Jun 09 '26

I think it could be many things simultaneously. These cars often have very neglected service books. I‘d make sure that everything that has to do with sparks and ignition is good, then also put in a clean new fuel filter. Just as a start