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Toyota Repair/injection pulse


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

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?

Toyota Repair

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Ted Ritter


I have more than 28 years experience as toyota technician, I will be able to answer most questions related to the Toyota product line up to the present year models,I am located in the US but welcome questions from other regions of the world. When asking a question please provide specific information: year,model, engine,transmission information. Provide as much information as possible including a brief repair history if possible. I have been a volunteer here for more ten years an have answered over 16,000 questions helping Toyota owners with their problems and save thousands of dollars without any compensation, some of my answers are published on many other websites including google and various automotive forums. DONATIONS ARE VERY MUCH APPRECIATED, IF YOU HAVE RECIEVED HELPFUL INFORMATION PLEASE MAKE A DONATION. AS OF TODAY (JULY 22, 2014) ALL REQUESTED GRAPHICS, ILLUSTRATIONS, DIAGRAMS, PHOTOS, WILL REQUIRE THE MINUMUM DONATION UP FRONT.


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