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fi light, need help

7K views 31 replies 8 participants last post by  SubSailor 
#1 · (Edited)
Hey everyone, I have a weird situation with my bike. When I turn the key on, fuel pump primes and the fi light blinks steadily. when I start the bike it does the same thing. thought maybe it was flashing a code, but its just a steady blink. When i put the bike in gear and take off, the light stays on. the light stays on the whole time its running after that, and when i start the bike later the cycle repeats itself. any ideas how i can check this out and figure out whats going on? my bike has the flapper mod and pair mod im told, though I do not know what either one of those are... bike is an 02 rc51, no other mods that i know of. any ideas would be greatly appreciated!

edit: i just replaced the map sensor today as the previous owner said it was bad. the light still comes on. he said something about resetting the computer... any ideas?
 
#28 ·
aha I see. so I pulled the fairings off, all the connections looked good. I forgot to check the voltage going to the sensor though. i guess i will have to do that... the baro sensor is on the left side right in front of the radiator right? it has a 2 wire plug and a couple vacuum lines going to it... i couldnt tell in the manual from the picture whether it was on the left or right side, but i didnt see anything on the right side.
 
#29 ·
No. The baro sensor is located on the snorkel, near the front. Refer to diagram.
The item you mention is probably the vacuum solenoid controlling the flapper valve. It's mounted at the upper front of the left radiator.
Your bike may be backfiring due to a lean condition.
Maybe possibly due to the baro sensor being unable to determine exact barometric pressure. Or due to air/fuel ratio being towards the lean side.
 
#30 ·
My SP2 recently developed the same long blink Fi. Initially I thought it may be down to a poor connection as I also had a Dobeck TFi fitted (by the way, does anybody have experience with this unit?)

However, I remembered that with the much talked about flapper valve mod I had disconnected the vacuum hose to the valve and plugged it while waiting for the flapper valve cover to arrive from Dan Kyle Racing when I planned to remove the whole enchilada and clean out the snorkel.

Question is? Could this, would this confuse the BARO sensor?
According to most forums it seemmed like a worthwile mod?
 
#31 ·
I'd like to think that the baro sensor, short for barometric, is a funky name for an air-pressure gauge that feeds into the ECU to calculate fuel vs air-density. When Ram-Air effect kicks in air pressure goes higher than the one atmosphere and more fuel is needed per volume of air as there is more oxygen in it. This also works for going from really cold dry days at the beach to hot muggy days in the mountains.
The only thing that would mess up the effectiveness of the reading would be a leak past the sensor where compressed air through the snorkel would vent out and never reach the manifold at the same pressure.
 
#32 ·
The Baro sensor measures ambient air pressure at the snorkel inlet.
The MAP (Manifold Air Pressure) sensor measures air pressure inside the airbox near the intake manifolds.
The difference between the two tells the ECU how to offset the Air/Fuel ratio for altitude, ram-air effect, dirty air filter, etc.
However, it can only calculate the air/fuel ratio within the bounds of it's known digital map.
If any sensor fails, the system will default to a preset (limp home) value.
 
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