My mazda eunos will not rev over 2500rpm. And when I rev it over that the revs go up but straight back down again. Eg spluttering. But badly. I have changed the feul filter as it seemed it was being starved of feul that didn't work. Then I changes the air flow meter. And that has not worked. Am wondering if it could be the injectors??

SOURCE: my car idle dips to low RPM at a stop i give it gas it dies

Is the engine light on? Check the air inlet hose between the throttle body & MAF sensor for cracks or leaks. Try unplugging the MAF & see if there is any difference

SOURCE: Mazda Sentia 929 auto failure

Rebuilt gearbox probably... unfortunately!
If the HOLD light in the in strument cluster is flashing at you, it is giving you a transmission diagnostic code (like a kind of Morse Code). A transmission specialist or a Mazda Dealer will be able to read this code and plug their computer into the cars computer, and tell you what is wrong.

SOURCE: 2001 Mazda MPV that hesitates and chugs when you

check the oxy sensor operation if the sensor has failed the car will run rich and start to chug. this can also be a intermittent thing

SOURCE: My car mazda eunos was over heated , then just

cracked block

SOURCE: b2500 turbo diesel fuel pump diagram

Undo the fuel inlet Banjo bolt and carefully fish with a piece of wire bent at the end (as pictured) and fish out the filter (under the spring) wash and replace. Can be very fiddly, so patience is a must.