Injector Driver failure
#2
TECH Veteran
iTrader: (37)
Put a noid light on the ailing injector connector and it should flash when you crank the motor and tell you if you are good or not. Then check for 12 v at the injector connector and then use a voltmeter to verify there is not an open circuit between the pcm and the injector by putting it on diode check and hooking up the lead at the injector side and then on the pcm side with the pcm disconnected, the meter should beep and give the resistance of the wire you are checking. If all checks you either have an injector shorting and the pcm is shutting off the affected driver or a pcm failing.
#3
Originally Posted by 01WS6/tamu
Put a noid light on the ailing injector connector and it should flash when you crank the motor and tell you if you are good or not. Then check for 12 v at the injector connector and then use a voltmeter to verify there is not an open circuit between the pcm and the injector by putting it on diode check and hooking up the lead at the injector side and then on the pcm side with the pcm disconnected, the meter should beep and give the resistance of the wire you are checking. If all checks you either have an injector shorting and the pcm is shutting off the affected driver or a pcm failing.
#4
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The injector duty cycle would produce something between 0 and 13V
directly across the injector. Close to 0 at idle. You need to be careful
with digital meters, sometimes high frequency AC is not averaged like
old analog ones. But you would expect the voltage to be consistent
at idle with fixed RPM & MAP.
A failed driver will most likely fail open (no voltage across injector) or
shorted (full IGN voltage). If it's somewhere in the middle then the
driver is switching so probably close enough to right.
directly across the injector. Close to 0 at idle. You need to be careful
with digital meters, sometimes high frequency AC is not averaged like
old analog ones. But you would expect the voltage to be consistent
at idle with fixed RPM & MAP.
A failed driver will most likely fail open (no voltage across injector) or
shorted (full IGN voltage). If it's somewhere in the middle then the
driver is switching so probably close enough to right.
#5
"All Motor 9 Second club member"
iTrader: (60)
I'm not sure what symptoms you have or what sparked the concern, but I have seen people have injector issues after installing a tranny. The problem was that they pinched the injector harness when they tightened up the dipstick tube. It may be a long shot, but it's a thought.
Good luck!
Good luck!