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Discussion Starter · #1 ·
Hi, I'm finishing my last adaptations and I've already done some tests, the bike has a walbro 255 lph petrol pump and an FMU to increase the pressure at the moment of boost. My biggest problem is in the map sensor that hardly the turbo starts in boost I turn on the light bulb of the F1, I would like to hear some ideas to be able to finish my project successfully. Thank you
 

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I don't have a solid answer for you, but knowing how that light gets set, I'd say your best option is to ignore it or remove the bulb / disconnect it. With no access to tell the ecu to ignore the boost condition, it is what it is, or you'll give up rideability when not in boost.

I think it's technically not a MAP sensor but a MAF sensor. MAP reads pressure/vacuum, MAF reads air flow. MAP goes after the throttle plate, MAF, before ... generally speaking. It's seeing either seeing more air flow than the ECU believes it should see and can fuel for, or, it believes the sensor is damaged in some way. I'm not sure what the signal is from this sensor, but most are about 1-4.5 VDC. If it sees in excess of about 4.2VDC the programming sees a condition it cannot allow for. It is possible to build a unity gain amplifier to limit the peak. I can't say this would solve the problem without creating a bigger problem but it's my theory at the moment.
 
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Discussion Starter · #3 ·
I don't have a solid answer for you, but knowing how that light gets set, I'd say your best option is to ignore it or remove the bulb / disconnect it. With no access to tell the ecu to ignore the boost condition, it is what it is, or you'll give up rideability when not in boost.

I think it's technically not a MAP sensor but a MAF sensor. MAP reads pressure/vacuum, MAF reads air flow. MAP goes after the throttle plate, MAF, before ... generally speaking. It's seeing either seeing more air flow than the ECU believes it should see and can fuel for, or, it believes the sensor is damaged in some way. I'm not sure what the signal is from this sensor, but most are about 1-4.5 VDC. If it sees in excess of about 4.2VDC the programming sees a condition it cannot allow for. It is possible to build a unity gain amplifier to limit the peak. I can't say this would solve the problem without creating a bigger problem but it's my theory at the moment.
if i agree with you, i will try to stabilize the voltage and i will do some tests with the multimeter to see if it works better .thanks for your answer it is a valid occupancy
 

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if i agree with you, i will try to stabilize the voltage and i will do some tests with the multimeter to see if it works better .thanks for your answer it is a valid occupancy
It is really too bad they locked the ECU down like they did on these bikes. The upside to doing this with a Harley is that ECUs are readily available. Downside is that the VTX is by far the better platform for this sort of thing.

Whatever you find out with the FI light, let us know what you tried and how it worked. Having these answers archived on the board is a valuable tool for those that come after us.
 
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Discussion Starter · #5 ·
It is really too bad they locked the ECU down like they did on these bikes. The upside to doing this with a Harley is that ECUs are readily available. Downside is that the VTX is by far the better platform for this sort of thing.

Whatever you find out with the FI light, let us know what you tried and how it worked. Having these answers archived on the board is a valuable tool for those that come after us.
If I am waiting for the weekend to do some tests and any discoveries I will tell you. Thank you for your comments
 
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