[1987ss]

My tahoe is acting up again. its a 1999 with the 350 vortec with 138k on it.... its hesitating after driving for 2 hours.i dont know if the a/c plays a part in it cause the last few times it happened the air was running and it was parked ideling for about 45 min i tested fuel psi while truck was HOT and it was at 50psi at idle and 53psi under load. let it sit engine off for a few hours and psi when first started is 55psi.. had regulator changed 8 months ago [dealer] and fuel pump a little over 2 years ago with a oem part from GM.. is it bad again? Thanks

also.. when you come out in a.m. or after it has sat over night engine rotates more than normal before it starts..unless you turn key to on position with engine off for 15 seconds then it will fire right up.. left pressure tester on it over night a few times and it hold pressure it dosent leak it.. dont know if it helps any,just another issue i noticed.