Have a mazda 626 2000 4 cyl. when i run the car

1 trick to try is this. Turn ignition to run, disconnect battery negative terminal on battery, leave the ignition on for the entire time. Wait 1 hour than re connect battery with the key still on run position. Try to start car, if it starts and runs OK and doesn't shut back than it could been in brain lock. Turn off car and rearm security system. wait about 10 minutes than insert key and start if it continues to run than your probably OK. If it rearms starter disconnect than chip in key or the ring around ignition switch is bad. In that case a dealer will need to replace the part and re program the security system to accept the new part.

engine coolant temp sensor for engine control management out of range easy replacement its fitted in the cylinder head i think ? its a common fault hope this helps.

Check the glow plug circuit.

M.a.P. sensor, air leak in intake system, low or erratic fuel delivery

that is bollox,the dealer has 30 mins to recalibrate the system or it will shut down and need all he said,is he for real a mazda dealer.........or are you rich looking????? get it to another dealer,ask them to get 2 keys and recalibrate(assuming the first dealer has not caused a meltdown of the system.....)the problem you may have is they may not know about the 30 min rule...its to stop thieves from changing keys on stolen cars.......

Too low fuel pressure. Try spraying starting fluid while someone else cranks it. If it runs, you need fuel pump

check the mas air flow sensor(is this the 6 cyl) the sensor has a problem with the nose piece inside not moving enough to tell the ecm the propper air flow for the cold start,also check throttle valve for dirt build up around it-if its a four cyl repost

does the water pump run off the timing belt or auxillary (fan) belt? maybe timing belt has slipped some teeth?

I recently solved the very same problem on my tribute. I really needed a tune up, Plugs, fuel filter, pcv valve, cleaned throttle body, and mass air flow sensor.My problem went away, and engine runs great and idles perfect.. If you havent had a tune up recently maybe this will help you.

check the belt timing. could be firing early or late.