Hey, I just picked up a 90 Suburban with a 350 TBI, 4wd and it's massively over-fueling. Have replaced map sensor, fuel pressure regulator, o2 sensor, idle air control valve, rebuilt the throttle body, all to no avail. Running out of ideas, gonna pick up new egr valve and spark plugs tonight and see if that helps. ANY IDEAS???

 

Check the output on the TPS, I think at idle is should be between .5 and .65 volts and 5. volts at WOT