Bobby, that 2k resistor should not affect the pulse width; it's purpose is to provide parallel instruments with an isolated sample of the pulse-width to determine rpm and fuel flow.  Will be interesting to see what your test reveals.
Jeff

From:   Bobby J. Hughes <flyrotary@lancaironline.net>
Subject:        Re: [FlyRotary] Re: F/A and EGT data
Date:   Sun, 14 May 2017 12:46:00 -0400
To:     Rotary motors in aircraft <flyrotary@lancaironline.net>
        Message Header

Yesterday I remembered my rotor 1 primary injector has a connection to the EC3 for fuel flow and AFS engine monitor for RPM. I believe I place a 2k resistor between the injector and AFS and possibly the EC3. This may be affecting the pulse on / off time when manually changing the mixture. I'll test by disabling the primary injectors at a stable rpm, manifold pressure and F/A while observing EGT's.

Bobby
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