1996 GMC Jimmy the problem is its hard to start have to use starting fu

SOURCE: 2000 GMC Jimmy won't start

i had the same problem and replaced the fuel pressure regulator. Cost about $45 at advance auto store or about $90 at napa auto stores. Once i replace that my truck started right yup and runs like a champ

SOURCE: wath P1406 Code means on a GMC jimmy 1996,

It's an egr valve problem (exhaust gas return) egr position sensor.
Take off the egr valve and turn it over and see if there is carbon build up in the ports, if there is clean it out with a pipe cleaner and a little carbon cleaner, just spray a little into the ports and clean it out. If that doesn't cure the problem, then either the sensor needs replacing, and or the egr valve.

Testimonial: " thanks for yout help"

SOURCE: 1996 GMC Sierra 1500 XC 4x4 5.7 Hard To Start

It is probably the fuel pump. If I remember the number correctly, this fuel system needs about 50 lbs to open a valve.
Until this valve opens, no fuel gets to the fuel nozzels.