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Toyota Repair/injection pulse

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the injectors are controlled by the ECU, the ECU needs to see a couple of input signals or the injectors won't be turned on, these are the IGF and the NE signals, the IGF is the signal that tells the computer that there is spark to the spark plugs(which seems to be the case) the NE signal is an rpm input signal that lets the computer know the engine is turning over, if this signal is not there the injectors will not fire, there is a simple little test light available at most autoparts stores that plugs directly into the injector connector, it will flash if the computer is commanding the injector to turn on/off, if this does not happen the problem may be a loss of the NE signal or a bad ecu or a bad ecu ground or wire problem, there should be a steady voltage to one side of the injector connector, between 6-12 volts depending on whether an injector resistor is used, the other side of the injector connector is the on/off ground signal controlled by the computer which cycles the injector "ON" time according to engine demands.

i used this noid light and only flashes for 3 second while engine tries to run then shuts down. car has sat for 13 years so if injectors are plugged or shorted with rust would they cause this problem?...thanks i sent you another email asking how to check these igf and ne signals hope you can help me..thanks you

Answer
If the injectors were bad or corroded etc then the light would still flash, the problem is most likely a loss of rpm signal which in most cases comes from a signal generator in the distributor
What year and model is this and what engine does it have?

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