Car starting problem? on 1994 Subaru Legacy

have replace the fuel filter fuel pump fuel pump relay and battery sometimes it start and sometime it will crank but i have to hit the gas to start it

by in Madison Heights, VA on February 04, 2012
1 answer
ANSWER by , February 04, 2012
You need to do tests when the car is in a failed/no start mode. Check for fuel pressure (you will need a fuel pressure gauge and look up the specified fuel pressure for your vehicle). Remove the fuel hose that goes to the fuel rail and get a friend to crank over the engine to see you have adequate fuel volume (you should have approximately 1 pint of gasoline in ten seconds of cranking). Off course take proper precautions as gasoline is highly flamable. Next "listen" to the fuel injector. Using a mechanic's stethoscope (or use a long screw driver placing the handle end up to your ear place the metal tip end of the screwdriver against the body of the fuel injector), get a friend to crank over the engine while you "listen" to the fuel injector listen to each injector at the same point of the injector body. You should hear "click, click, click" as the injector is electrically opened and closed by the computer. If the injector is not being triggered you will not have fuel getting into the engine's cylinders. Also check for spark at the spark plug wire on cranking when the engine wont start. The engine needs to see crank and cam position sensor signals for the computer to start triggering fuel and spark.There is a company that independent auto repair shops get their information from, this same information is available inexpensively for people that work on their own cars.. The information is year make and model specific, covering repair procedures, torque specifications, fluid capacities and specifications, service bulletins, component locations, wiring diagrams ect.... Alldata is very easy to navigate http://bit.ly/AllData_Repair_Manuals_Online