Fuel injector driver
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Teching In
Joined: Jun 2016
Posts: 8
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Fuel injector driver Im going to start by how I believe the circuit works and then my symptoms.
Constant 12v power to one wire
Individual ground controls from pcm only when runninv
Correct?
My symptoms are #3 constanley on causing hydrolock.
All injectors have constant ground without car cranking
When blue pcm connection is removed no more ground to any injectors. So my wiring isnt bad. Check pin 3 Blue (fuel injection control #3) and it has ground with everything off.
#3 has been hydrolocking with 2 different pcms and 2 different sets of injectors.
Am i checking my circuit the correct way. I should only get ground to a single injector at a time when the engine is cranking of running. No grounds to any when not running?
Constant 12v power to one wire
Individual ground controls from pcm only when runninv
Correct?
My symptoms are #3 constanley on causing hydrolock.
All injectors have constant ground without car cranking
When blue pcm connection is removed no more ground to any injectors. So my wiring isnt bad. Check pin 3 Blue (fuel injection control #3) and it has ground with everything off.
#3 has been hydrolocking with 2 different pcms and 2 different sets of injectors.
Am i checking my circuit the correct way. I should only get ground to a single injector at a time when the engine is cranking of running. No grounds to any when not running?
You should not be able to "see" the ground without an oscilloscope when the engine is cranking or running, as it happens in about 3milliseconds (.003 seconds). Since the 12v is applied all the time, anytime you "see" ground means that both are present (12v + ground) and so the injector is open, which sounds incorrect.
All theory aside, if you rule out the PCM and the Injector, the only thing left is the wiring. So its the wiring. Just run new wires straight to the ECU in the designated location and verify the wiring is bad.
All theory aside, if you rule out the PCM and the Injector, the only thing left is the wiring. So its the wiring. Just run new wires straight to the ECU in the designated location and verify the wiring is bad.
9 Second Club
Joined: Nov 2003
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From: Norn Iron
Im going to start by how I believe the circuit works and then my symptoms.
Constant 12v power to one wire
Individual ground controls from pcm only when runninv
Correct?
My symptoms are #3 constanley on causing hydrolock.
All injectors have constant ground without car cranking
When blue pcm connection is removed no more ground to any injectors. So my wiring isnt bad. Check pin 3 Blue (fuel injection control #3) and it has ground with everything off.
#3 has been hydrolocking with 2 different pcms and 2 different sets of injectors.
Am i checking my circuit the correct way. I should only get ground to a single injector at a time when the engine is cranking of running. No grounds to any when not running?
Constant 12v power to one wire
Individual ground controls from pcm only when runninv
Correct?
My symptoms are #3 constanley on causing hydrolock.
All injectors have constant ground without car cranking
When blue pcm connection is removed no more ground to any injectors. So my wiring isnt bad. Check pin 3 Blue (fuel injection control #3) and it has ground with everything off.
#3 has been hydrolocking with 2 different pcms and 2 different sets of injectors.
Am i checking my circuit the correct way. I should only get ground to a single injector at a time when the engine is cranking of running. No grounds to any when not running?
Pull the rails from the intake with the injectors still attached ( if clips to secure them are present ) Key on and allow the pump etc to prime and crank it over so you can get a true visual of what is happening.
Are you saying #3 will always hydrolock....even if the injector is not plugged in ? Or only when the injector is plugged in ?
As you say, 12v ign feed to one side, ecu to the other. At rest this side may also appear to be at 12v or near if you test between it and ground. To fire, the ecu will ground it.
A noid light or LED etc, or even digital multimeter will give you some sort of visual reference if the state of this wire is changing, or if it was permanently on etc.
