K2500 7.4L

1994 GMC Suburban • 180,000 miles

Had a bad fuel pump swapped it out now (bad fuel pump for sure worked intermittently tested out of tank works sometimes and not others) now truck start but immediately if I disconnect vacuum hose from map sensor the truck will idle for a little bit maybe 2 -3 mins idle increases then truck dies I have used my multimeter to check all sensors and modules and all have proper voltage during testing also black smoke from exhaust it seams like for a little while with map vacuum disconnected it gets proper amount of fuel and the fuel cuts off also good fuel filter thank you for your help Scott
April 14, 2013.

What is the exact fuel pressure?


Apr 15, 2013.