Mazda Repair: 2002 mazda626, combustion cycle, mazda626

Question
QUESTION: the battery, starter and alternator is fine - electrical no prob -  car does not start intermittently. what is the problem

ANSWER: do you have spark and fuel?


---------- FOLLOW-UP ----------

QUESTION: I'm sure i have spark - my guess is fuel, more likely fuel filter, pcv valve?? or fuel injection cleaning??? still unsure...thx!

Answer
fuel filter is only to filter the fuel it wouldn't stop your gas from not running, pcv valve is used as an emissions device to reintruduce unspent gas back into the combustion cycle again wouldn't stop your car from running. it could be your injectors but i'd start at your fuel pump. put the car in the run position and listen for a humming coming from the gas tank to conferm it's working