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02 E does not go above 1V. The readings I gave you were MV. The problem is when the 02 goes lean .5-1.5ish MV, the PCM should call to richen the system up, but is does not. Long tern fuel trim seems to hang aroun 162-65 on a hot engine, short term fuel trim starts at 128 and sometimes goes to around 134.
Vacuum at 2500 in park is around 20inches.
I previously checked the MAP port for vacuum, OK. According to the specs for this truck, the fuel pressure should never go over 13psi (right off Mitchell). It is a brand new fuel pump, as previous has low pressure issue. Filter is not that old, and if plugged or if pressure regulator is malfunctioning, why do I never see fuel pressure at throttle body so much as waver lower than 12psi? Also, many times the lean condition will start just off idle so bad so that truck wil fall flat on its face and stall. There should not be a need for more than 13psi fuel at that low point in the RPM range. I was going to do a pump volume test, but really it should not be necessary as the pressure does not fall off.
New fuel injectors rebuilt by a good company. Engine runs the same on these injectors as the old leaky ones. Spray pattern on these is clean, old injectors dripped enough to run after key shut off. Also these injectors came first of a good running boat, and injector company verified they would work on the truck.
MAP has been replaced, I have checked the MAP circuits, and MAP reads correctly on scan tool at every RPM. I have even disconnected MAP and other sensors to now avail.
I am sure all the sensor parameters are within their spec'ed ranges. I will try the pump dead head and pressure test.