B737-700
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 190; Flight Crew Type 4573
Situational Awareness
Deviation - Altitude Overshoot; Deviation - Altitude Crossing Restriction Not Met; Deviation / Discrepancy - Procedural Clearance; Inflight Event / Encounter CFTT / CFIT; Inflight Event / Encounter Unstabilized Approach
Flight Crew Executed Go Around / Missed Approach
Human Factors
We were on a right base to final for Runway 26 at 4;000 feet MSL and 210 KIAS.  We were cleared for and accepted the Visual Approach. We were directed to maintain 170 KIAS to PRUNN.  As we intercepted final course in LNAV mode; I queried the Pilot Flying (PF) about selecting VOR/LOC in preparation for selecting APP.  He stated that we could continue in LNAV as he proceeded to program the 170 KIAS speed into the FMC for PRUNN.  As we crossed JAGAL; I stated that he should begin the descent to 3;000 feet MSL. At this point we were clean; 0 Flaps and Landing gear up.  I again called for the descent; at which point the PF came heads up; noted our position; and called for landing gear down; extended the speed brake and nosed the aircraft over in an attempt to acquire the glide path.  We continued past PRUNN well above 3;000 feet MSL with landing gear and speed brake extended.  Approaching approximately 2;500 feet - 2;300 feet MSL; we both commented that a go-around would be required.  Immediately thereafter; the go-around command was called at approximately 1;300 feet - 1;200 feet AGL.  As we began to execute the go-around; the GPWS alert PULL UP sounded and I noted a descent rate of approximately 3;500 feet FPM.  The go-around; approach and landing were uneventful.Preventative Measures: Continue to emphasize use of the appropriate level of automation as well as when it is and is not appropriate for the Pilot Flying to be heads down programming the FMC.  Consideration should also be given to standardizing procedures of who (PF vice Pilot Monitoring) should be responsible for programming and executing the FMC.  One option would be to have the Pilot Monitor (PM) input FMC changes; PF crosscheck; PM execute.
B737-700 First Officer reported an unstabilized approach to PHX airport that resulted in a GPWS alert and a go-around.