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Toyota Repair/Toyota 4Runner 1985 Injectors EFI


QUESTION: My 1985 Toyota has a 22RE  EFI  system and a A/Trans    . I have re-bilt the22 RE from top to bottom . Put in new injectiors OEM  changed the EFI computer  EFI relay switch Fuel pump regulator My injection system pours raw fuel in too the cylinders and out the Ex-manifold .This happens when  I  turn on the key too start position ( not the starter ) . I have had electrical  problems with this 4Runner four a long time due to too many owners in the past years . Ihave fixed all but one and I think created my own problem . Mabe it happend when Ireplaced the fuse block . here is my question  , dose the EFI relay control the open an closing ( or the pulse ) of the injectiors . I have taken a oem meteor  two all 4 plugs and got a reading of 12 Volts on both pins in the plugs . Also checkout grounds , good .
I hope you can help   .
Thankyou   Tim

ANSWER: Hello, the EFI relay powers up the circuit opening relay and battery voltage to only one terminal of each injecto connector, it does not provide injector pulse voltage, this is done by the computer, it grounds the other terminal on the injectors to tUauDo you have a wiring diagram urn them on and off with the pulse signal, if you connect a testlight to both terminals the light should flash when cranking the engine. The problem seems to be that there is voltage to both sides which can keep the injectors open.
Do you have a wiring diagram? You'll need to find why the other side is getting battery voltage, I think the constant voltage wires to the injectors are black/red but to be sure I'd have to look for a diagram in my files, I can do that tomorrow

---------- FOLLOW-UP ----------

QUESTION: tim here hope your day is going well . With your help I have found 10.58 Volts passing through the injectiors
down to NO 10& NO 20 to the ECU . Theise wires are white ( pulse side ove the injectiors ) blue&yellow
supplys power via the resistour . black/red supplys power to the restiour via eicnitor ( 12volts ) .
he injectiors all have 02.6 ohms ( 200 ohm scale ) all 4 fall in spec. Question is , dose the ECU @ NO 10 & 20 excepts the voltage & thin axs as a switch to create a pulse ? .

Hello, yes those wires coming from the ECU terminals 10 and 20 should pulse to ground, there should be no voltage, all the computer does is provide a ground on/off signal to the none voltage terminal of each injector, the other wire has constant voltage so the injectors are switch on/off by the computer ground signal which is based on various input sensors. Back probe these two connectors on the computer and use the ohm meter one connector at a time, ground the meter to body ground you should see a fluctuation of the meter, if so then the computer is doing what it's supposed to, the next step,do the same thing except connect the ground of the meter to the E1 terminal on the computer, it should do the same. If not check ground between the E1 terminal and body ground.  

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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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