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Discussion Starter · #1 ·
2003 1800R Desmoged, pair valve removed, ground fix, Vance and Hines big shots, K and N filter. FPR is new.

Fuel flow test shows 3.5 ounces in 10 seconds! Not sure how the fuel pressure is I do not have a gauge to test.
Could this cause a rich condition? Plugs have some carbon build up, soot inside both exhaust pipes, and poor fuel mileage (21 MPG average over 4 tanks) 90%in city.
My thought is this will cause weak fuel atomization?

Bike runs good and has good power. Only thing is at low speeds I feel some hesitations while cruising around.

Jackie
 

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Do you have a fuel manager? Power commander or Cobra or ?? Did you remove the dust cover from the FPR when it was installed,? Is the FPR vacuum good??? Your X is passing a lot of gas. Pull a spark plug out, turn on IGN, do not crank, do you hear or smell fuel spray??? Do the Ground fix..
 

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Discussion Starter · #4 ·
Do you have a fuel manager? Power commander or Cobra or ?? Did you remove the dust cover from the FPR when it was installed,? Is the FPR vacuum good??? Your X is passing a lot of gas. Pull a spark plug out, turn on IGN, do not crank, do you hear or smell fuel spray??? Do the Ground fix..
No fuel manager, FPR was put on @ November of last year pretty sure I removed everything before install.
Line to FPR has @ 12 inches of vacuum at idle. Very faint sound can be heard from spark plug hole when cycling the key.
No fuel in the oil and no fuel in the FPR vacuum hose.

Jackie
 

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Leaking injectors or a grounded wire at the cable harness clip. You could disconnect the ECM connector and pulse the injector wires with a Ground. How to Step by Step 1800 section with diagram of the ECM and the wire function. I will add more info, Black/white wire is +12volts when IGN On and Kill switch in Run position, feeds injectors, IGN coils, ECM.
Listen for injector clicks. Someone also mentioned seeing a injector spray from
throttle body I presume.

Pink/Yel and Pink/Blue are the Injector wires at the ECM.
ECM normally pulses Ground to IGN coils, Injectors.
YOU will provide a Ground to trigger the injectors.

Fuel flow is normally 6.4 oz US in 10 seconds.
Your MPG is low so fuel is going somewhere...
 

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Discussion Starter · #8 ·
Fuel flow through return hose is only 3.5 ounces in 10 seconds. I have checked this 5 times with same results each time.

Jackie
 

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Discussion Starter · #11 ·
Checked fuel pressure with FPR vacuum hose plugged up has a steady 50psi.
With vacuum connected bounces around between 40 and 50psi.
 

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That is about right. WOT low vacuum, higher psi gives it a richer mixture. Cruising - high vacuum reduces psi. When you pop off the ECM conn, you can also check voltage that is going through the injector. Just about the same voltage as the Black/white wire..
 
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