car intermittently starts,change distributer cap, roter, coil,fuel pump, fuel filter, took out aftermarket alarm, car will run for months sometimes, sometimes it fails when driving and sometimes the engine turnover kinda starting but shuts right back off, its not because its getting too hot because sometimes it sits for a week or 2 and still wouldent run. I don know what else to do , please help.
94 celica intermittingly starting on 1994 Toyota Celica
by ikhan2424 in Miami, FL on August 01, 2009
ANSWER by patrick mannion , August 01, 2009
The only way to figure out why your car is intermittently failing to start is to get the car to fail, and then have a friend crank over the engine and test to see if you have spark at the spark plug wire, (that would indicate the ignition system is OK), then crack open the fuel line at the fuel rail and see if on cranking the engine is receiving fuel. If you can determine this and know the engine is mechanically sound (it runs sometimes so must be) then you have narrowed down where to look diagnostically. You will need a wiring diagram and a good voltmeter to do meaningful test. It could be a bad main relay, failed sensors in the distributor (I have seen this cause your type of problem on Toyotas), a bad ignition switch or many other things. Get a wiring diagram, study it and know where to look for voltage when the car fails to start and run.