Fuel Primer does not shut down
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Fuel Primer does not shut down
Not sure if I am calling it right, but lately I have had my fuel pimer run and not go out...I have a 97 RK with fuel injection...when you turn on the key you get the primer buzzing and than it goes out....now it goes out and comes back on and does not shut down.......is this normal????I was running at high RPM's at stop lites and turned down the throutle screw to bring them down...they have come down but again now I got the buzzing
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yes the fuel pump..it always comes on when the ignition switch was turned on and always went off after a few seconds...now it goes off and than rite back on..I just never heard it before and now I am hearing it...is it norm or am I just freaked out
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Joined: Aug 2007
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From: NW AR
No, fuel pumps turn on and stay on when the vehicle is running. Pressure is regulated by ... wait for it ... The Fuel Pressure Regulator. On the HD EFI systems I've seen (Buell, actually), the regulator is stuck on the end of the fuel pump and fixed, not vacuum linked. I built mine differently, more like a conventional automotive EFI system. Anyway, EFI systems typically turn on the fuel pump when the ignition is first turned on to purge the fuel line of any air that might have been in there and to fire a little bit of fuel for priming, then they turn the pump off until the motor starts cranking, at which point they turn the pump back on until the motor stops. That's how every system I've run across works, including the one I built.
So, if you used to hear the pump come on, then go off until you crank it and now it is behaving differently, I'd say something has changed, and that is never for the good. There is a procedure to check your ECU for trouble codes. I don't know what it is, but I'm sure it is in your factory shop manual and probably on the site here somewhere.
So, if you used to hear the pump come on, then go off until you crank it and now it is behaving differently, I'd say something has changed, and that is never for the good. There is a procedure to check your ECU for trouble codes. I don't know what it is, but I'm sure it is in your factory shop manual and probably on the site here somewhere.
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From:
there is a possibility that the fuel hose INSIDE the tank has developed a pin sized hole due to rubbing or age..this may not permit the correct pressure to be maintained...if tank is full of gas you may see bubbles as pump is trying to maintain pressure...if this is the cause the bike may cut-out as fuel level in tank falls below level of the hole in the line..once gas tank is filled it would run again.. idle adjusted at throttle screw? do you mean the friction screw (poor mans cruise control) or some after market throttle assembly?..the idle thing has me confused unless someone was trying to compensate for leak during warm-up...i believe the regulator on that year of bike (if you have two fuel hoses from tank) was located at throttle body (induction module assembly) between cylinders...just to be clear when you power the bike -up and do not start... the pump should run for about 3-4 seconds and then stop...it should not start pumping again while bike is not running.
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it does run for 3 or 4 secs and than goes out......again my bike used to rev out of control...would be sitting at a lite and in nuetral and the revs would be cewl..do not have tach so not sure on the revs, but they were nice and regular...but than out of nowhere she would start reving high..and I mean highhhhhhhh........it would be ok gettiing out of the city running the gears but at stops it was horrible...than after the bike sat for a while she would be normal again.....I did back off the throuthe screw a bit and unplugged the throutle senser that sits between the jugs...checked for any bent prongs in the harness...after that she reves nice and low..almost to the point of stalling out, but she sounds good and runs great....but it was after this that I noticed the pump constantly running, where before I never heard it...only at turning the ignition on and yes that would be 4 or 5 secs....maybe I am just being a bit paranoid here...........and on the other note I usually run my fuel rite to the warning light and the scoot never missed a beat
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From:
ok,
would think that your pump is ok!
if rpm's are off at idle consider review of engine temp. sensor.
would think that your pump is ok!
if rpm's are off at idle consider review of engine temp. sensor.
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