Injector selfsquirt problem
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From: finland
Injector selfsquirt problem
Hello everybody.
I took my S4 back on the roads about a month ago, after winter... Everything was fine, until yesterday I have got the same problem I had at autumn last year:
The injectors will start squirting when I have an ignition turned on, but the engine is not running. If I shut the engine and then turn ignition on, the injectors may start to squirt gas into engine. When I take the ignition key off to my pocket the injectors are still squirting. I have to cut the power off from the battery or start the car again. (it will not help if I turn the engine with starter, but not let the engine get started)
So what is wrong with my car?? Can someone help?
I have reconditioned LH brain from the 928ecu-repair Theo @ the Netherlands, so it is fine.
The LH Relay (that 53 marked one....are there other relays for the LH system?) is ookay, I took the cover out of it and checked the internals...nothing wrong there. Where the injector pulses come from? LH brain will send them, but where they go next? (straight to injectors or something before them?)
The problem will not apply every time I turn the ignition on. I think it applies every time when the fuel pump builds a pressure to the fuel system before cranking the engine....maybe, not sure though.
I took my S4 back on the roads about a month ago, after winter... Everything was fine, until yesterday I have got the same problem I had at autumn last year:
The injectors will start squirting when I have an ignition turned on, but the engine is not running. If I shut the engine and then turn ignition on, the injectors may start to squirt gas into engine. When I take the ignition key off to my pocket the injectors are still squirting. I have to cut the power off from the battery or start the car again. (it will not help if I turn the engine with starter, but not let the engine get started)
So what is wrong with my car?? Can someone help?
I have reconditioned LH brain from the 928ecu-repair Theo @ the Netherlands, so it is fine.
The LH Relay (that 53 marked one....are there other relays for the LH system?) is ookay, I took the cover out of it and checked the internals...nothing wrong there. Where the injector pulses come from? LH brain will send them, but where they go next? (straight to injectors or something before them?)
The problem will not apply every time I turn the ignition on. I think it applies every time when the fuel pump builds a pressure to the fuel system before cranking the engine....maybe, not sure though.
Under the Lift
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From: Buckeye, AZ
The injector firing signal is a ground pulse from the LH pin 18 directly to all 8 injectors in 2 wire bundles, shown in blue below. The other side of each injector lead is 12V from the LH relay output pin 87, shown coming in as the red lines. The LH relay is signaled by pin 21 on the LH brain.
If the injectors "click" when the ignition is on but the car is not running, this is a sign of a bad LH brain. The fact that they continue to fire with the key removed means there is another problem as well, maybe a bad ignition switch. There is probably a more exotic way to account for power to the fuel injection system with the ignition key removed, but I don't know of it.
If the injectors "click" when the ignition is on but the car is not running, this is a sign of a bad LH brain. The fact that they continue to fire with the key removed means there is another problem as well, maybe a bad ignition switch. There is probably a more exotic way to account for power to the fuel injection system with the ignition key removed, but I don't know of it.
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Joined: May 2004
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From: Philly PA
Thats what i was thinking Bill good call, Its possible the brain has failed in conjunction with the ignition switch.
So first disconnect the battery and replace the ignition switch, see if this cures your problem if not then the brain is next
So first disconnect the battery and replace the ignition switch, see if this cures your problem if not then the brain is next