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Yugi
Posted on Wednesday, August 21, 2013 - 08:16 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

My low fuel light goes on and off all the time, while the tank is full. I'm running EBR ECM,Compufire VR. I checked the fuel pressure and it's around 410-420 at idle. What is the issue?
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Smoke4ndmears
Posted on Wednesday, August 21, 2013 - 09:06 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

thermal resistor in the fuel pump probably. either replace the fuel pump or live with it :/
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Yugi
Posted on Wednesday, August 21, 2013 - 09:22 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I can do it under extended warranty.
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Smoke4ndmears
Posted on Wednesday, August 21, 2013 - 09:59 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

even better. 08 or 09?
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Zac4mac
Posted on Thursday, August 22, 2013 - 12:23 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

09 CR
Yugi - the "dealer fix" is a fuel pump assembly.
If you're doing it on your nickel, there are a couple of fairly cheap alternatives.

Beancounters again, a good thermistor won't drift like this.
Mine drifted to a higher resistance until it was out-of-range and the ECM threw a code.
I am assuming they all will drift high, but statistically some will drift low.

Intimately familiar with this issue...

Zack
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Yugi
Posted on Thursday, August 22, 2013 - 01:39 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Zack,

So what's an alternative fix?
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Fordrox
Posted on Thursday, August 22, 2013 - 11:56 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Pull the fuel pump, replace the thermister on the pump assembly and reinstall the pump. i have no more detail than that as i have not personally done it yet, but my Uly needs it done.
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Zac4mac
Posted on Saturday, August 24, 2013 - 01:19 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

The easiest fix for the thermistor is to wire a low-ohm potentiometer(variable resistor) in parallel then adjust so the total resistance is back in spec(800 - 1400 Ohms IIRC).
Also IIRC, pins are 1 & 4 on the connector under the rider's seat.
Resistors in parallel will have a total resistance lower than the lowest one. R1 X R2/ R1 + R2 = RT
The one failed fuel sensor I had, had drifted high(2400 Ohms at 70 dF).

If your pump goes, you can replace just the pump, it's fairly common.

Zack
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