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Injectors Always On

Old 03-25-2005, 03:22 PM
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The active wire from the injectors to the battery (B+) always has a charge going through it regardless of the ignition position. Anyone know why this would be happening? thanks
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Old 03-25-2005, 08:29 PM
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trace the wire down. the stock setup is like this:



battery->30amp egi fuse->main relay->injectors->ecu->ground



the stock wire is black with yellow



and if its stuck on then id look at the main relay, maybe its suck on?
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Old 03-25-2005, 10:35 PM
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The injectors always get 12v constant from the battery/relay side. Injector control/switching is from the negative/ecu side of the wiring equation.

How do you know that the injectors are always on?

Trace the ecu side of the injector loom and verify they are correctly installed.

Use a noid light to verify injector operation. (These can be had at most auto stores).



TESTING WITH NOID LIGHT S4/S5/S6 motor



S4/5 - Remove CAS from motor, but make sure it is still connected to the loom, remove both primary injector clips (this will prevent the motor from flooding whilst testing). Install noid light into any primary injector connector(primary inj=lower injectors), turn on ignition key then spin CAS with your hand and watch the noid light flash; they should (verifying injector operation). The CAS has to be spun quickly and this will verify the circuits operation. If everything checks out then your problem might be stuck/dirty injectors from a motor sitting for awhile causing the injectors to be stuck open.



S6 - If your motor is a S6 (no CAS) but uses crank sensor pickup on front pulley then just disconnect the primary injectors and install noid light as stated above and have someone crank the engine so you can verify injector circuit operation (test both connectors).
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Old 03-25-2005, 11:24 PM
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The motor is a 1996 13B-RE. As far as the microtech instructions go....we've done everything correctly. As for what i originally said.....the injector always has a positive charge. Its only supposed to be positive when the ignition is in the "on" position. When its in the "off| it should be producing a negative charge but its not. Its still positive. All the ignition wiring is correct......we traced every wire. Weve been using one of those noid lights and its always turning on. I cant find any wiring diagrams or anything at all for this motor either. Im at the final stages of this swap and im at a point where i have a problem and no one has really been able to help me. So thanks very much for your advice. So it could be a relay stuck in the on position? And yes the ground wire is black. Please get back to me........as of right now....you guys are my only hope.
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Old 03-26-2005, 03:37 AM
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Type of microtech? We will start from there to diagnose your problem. Somehow I knew that a EMS was involved with the problems you were having.
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Old 03-26-2005, 12:42 PM
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Im running a microtech LT-10 in my car. Came with ignitor and bosch coils. Wiring has been real long and drawn out because of the lack of a wiring diagram. I cant find much info on this computer or my engine.
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Old 03-27-2005, 11:23 PM
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I have a microtech LT10S with the X4 box the ecu always provides a positive the the injectors it is the negative that gets pulsed to fire the injectors. as long as the ecu is on the injectors will have a constant 12V. now if they are firing constantly then you might be having ecu issues.



And why did you not have a wiring diagram did you buy it used?
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Old 03-27-2005, 11:44 PM
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yes the only way to know for sure before actually trying to fire the injector itself, is to hook your ground lead to the appropriate ground for that injector, then hook the posative lead to the posative wire for that particular injector (or any would do, actually). only then will you tell if the circuit is closed all the time.
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