1987 Chevrolet Blazer • 58,000 miles

I have 1987 chev s 10 blazer with 2.8 eng. Starts and runs at idle just fine. When u acccelerate to about 20 mph the engine just looses all power, just like severe exhaust restriction. Had exhaust checked only has 1lb back pressure. I have changed I A C motor and T P S. Fuel pressure builds up to about 14 psi, while idling, but falls to zero when u shut engine down. Any help would be helpful. Thank u
July 2, 2013.

If the fuel pressure drops quickly when you shut the engine, there must be a leak somewhere in the fuel system. Have you checked for that? Also, does the engine rev normally in neutral? Have you checked for vacuum leaks around the engine compartment as well as the intake manifold?

If u block off return line to fuel tank pressure will hold at 14psi. Cannot locate any air leaks around tb, or intake. Rebuilt throttle body. No improvement. Cleaned all body to frame grounds. Need wiring diagram for ecm, and under hood. To make sure I have found all grounds for the elect system. Engine acts like it is running out of fuel when throttled. Will act up a little when in neutral.

Jul 4, 2013.
I don't know why, but this just showed up in my mail. Sorry it has been so long. Have you had any luck with the issue?