1992 gmc 1500 5.7 tbi 350....damm thing ran fine for a day then died and would start but not stay running I replaced the distributor cap rotor spark plus ignition coil and ICM, and the fuel filter still nothing....I unplugged the vacuum line from the map sensor it started and ran better but only for a few seconds then it would rev up and die....no codes I have tested the IPC and throddle position sensor and the map sensor all is good and only runs like i said with the vacuum unplugged from the map sensor I can’t figure this out I am out of options and out of money

 

fuel pump? Need to check pressure