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docaudio
05-23-2006, 09:22 PM
I've got a Stealth Ram system and whenever it powered up (battery hooked up and fuse in place) The fuel pump cycles to keep pressure in the fuel rails when ignition is off. This does not happen all the time, but often enough to be anoying. Every thing else seems OK. I have to pull the fuse when I shut it off. Any ideas?
Thanks,
Bill

andrewb70
05-24-2006, 12:00 PM
I've got a Stealth Ram system and whenever it powered up (battery hooked up and fuse in place) The fuel pump cycles to keep pressure in the fuel rails when ignition is off. This does not happen all the time, but often enough to be anoying. Every thing else seems OK. I have to pull the fuse when I shut it off. Any ideas?
Thanks,
Bill

Bill,

What your describing is not possible with the Commander 950 if the pump is wired up properly and everything is in working order. The signal to run the pump is only given when the ignition is turned on to prime the system. That length of time is set in the Hardware Settings>Engine parameters. The default value is 4.9 seconds. After that the only way the pump will run is if the Commander sees an RPM signal.

I would double check your pump wiring to see if your relay is bad and is sticking.

Andrew

TD509EFI
05-25-2006, 10:29 AM
Check your wiring to the ECU to make sure it's not getting 12v with the ignition off. Normally, the pump will run for five seconds before shutting off if the the engine isn't running. If you also have a slight leak fom an injector(s) , the combination of having a constant 12v source and the leaking injector will allow the pump to cylce on and off as described.

Otherwise, as Andrew mentioned, it shouldn't be happening.

John

andrewb70
05-25-2006, 12:32 PM
Even if the Commander is seeing a constant 12v sourse, the ECU needs an RPM signal to trigger the fuel pump relay. This is a safety feature so that in the event of an accident where the engine shuts off, then so will the fuel pump.

Andrew

docaudio
05-26-2006, 08:01 AM
Thanks guys!
I'll check the relay and wiring. This has been doing this since first running the engine on a test stand with original harness and also after installed in car with a re-dressed harness. I hear the relay clatter sometimes and also it can be quiet for hours. I just don't leave the car with the fuse installed for any length of time.
-Bill

andrewb70
05-26-2006, 12:12 PM
re-dressed harness.
-Bill

What does that mean?

Andrew

docaudio
06-14-2006, 10:43 PM
Sorry to snooze on the response...
'Re-dressed' is what I call a harness that has the cheap slited plastic tubing removed and is redone with a high-temp braided covering and shrink-wrapped ends. It looks a whole better than stock and I also corrected some wire lengths in the process.
-Bill