Welcome to A to Z Express Mobile Mechanics
MY CAR CRANKS BUT WON'T START. WHY?
Before the introduction of computerized engine controls, diagnosing a no start condition was very easy. In order the car to start it needs four basics things that never changed. It needs fuel, it needs air, it needs spark and exhaust.
First thing a technician will check if battery is fully charged and if engine cranks.
12.66 volts = 100% charged
12.45 volts = 75% charged
12.24 volts = 50% charged
12.06 volts = 25% charged
11.89 volts = 0% charged
If engine cranks but just does not start we need to do a basic checks:
Checking for spark
While you crank the engine observe if spark is present at the end of ignition wire or ignition coil.
Checking for fuel
Connect fuel pressure gage and crank engine to verify that fuel pressure is present and is into manufacture specifications.
Checking for air
After air filter is removed check the intake manifold for restrictions.