16
Coil Test - Fuel Injector Application
Peak Amps is the peak current driving
the injector. It is regulated by the driver.
Typical peak readings are from 1 to 4
amps for a current regulated injector
driver, and about 1 amp for a resistance
limited injector driver.
Build Time, is the time it takes the
amperage to reach its maximum. Build
Time is affected by the solenoid and pintle movement. Shorter
Build Time can be caused by a solenoid winding short or an injector
that is stuck. Longer build time could be from a bad driver or wire
connection.
Drive Time is the time the injector is actively driven. Use momentary
wide open throttle to see the Min and Max readings.
Analysis of Test Results
In general, a difference of 1 amp between injector banks on
resistance regulated injectors indicates that one or more injectors
is faulty in the bank with the higher amperage draw. In a current
regulated system, look for build time to be longer on the bank with
an open or high resistance injector. Build will be shorter on the
bank with a shorted injector.injector pattern.
LOBAT
MAX
MIN
PEAK
AMPS
BLD
HOLD
REL 0
mS
Peak Amps/Build Display
