1998 GMC Sierra Starting problems

Engine Mechanical problem
1998 GMC Sierra 6 cyl Two Wheel Drive Automatic

Hello,

I have a 98 GMC 1500 Siera, 4.3 Vortec eng (V6) 160,000 mi. Over the last two weeks, I have noticed that it was getting harder to start in the Mornings. Battery OK, Starter OK, but would not crank until after 8 to 10 tries.

As of yesterday it wont start at all, unless I use Engine starting fluid then it cranks immediately, and seems to run OK

I began trouble shooting by doing the following:

Listened to hear fuel pump activate. It did
changed fuel filter, changed fuel pressure sensor, Cleaned airflow sensor, Changed Air filter, cleaned the Throtle Valve, and changed the MAP sensor.

None of the above worked. (HELLLLP!)

is their something I missed? Or should I now change the fuel pump (OUCH!)


Rick