Grand Cherokee RS problem

Hello.  I'm having a problem with the RS on my 02 Grand cherokee.  It's a 4.0L and a Viper 791xv.  When remote started, it won't start on the first and sometimes the 2nd attempt (when it's cold).  It only does a partial crank for a fraction of a second.  Then it will reattempt to start and start just fine.  It's never not started, it just doesn't start until the 2nd or 3rd try.  It doesn't sound very healthy for the motor to me either.  I've adjusted the crank time to almost 2 seconds.  I'm not sure what else to try.  Any help is appreciated.  Thank you.

Thanks, I used the fuel injector wire option for the tach.  It should still be in tach mode.  If I remember correctly, it does this in both tach and voltage sense modes. 

Yeah, I changed it from tach sense to voltage sense and adjusted the crank time to see if that made a difference (it didn't).   I did learn the tach successfully before I changed it to voltage sense.  And yes the antitheft is bypassed.  Like I said when it starts, it starts just fine, but only on the 2nd or 3rd try.  It starts just fine with the key.   It seems to be worse when it's cold, and sometimes when the engine is still warm it might start on the first try. 

It jerks and makes a sound almost like there's something holding the motor from cranking.   That's the best I can describe it.  I do know the crank is turning though.  I'm almost wondering if it's not the alarms fault.