On my 1996 Toyota t100pickup with 3.4l v6, check engen lite come on and truck started stuttering like starving for gas, tried to retrieve codes but it keeps saying check connection. All fuses are good
Could well be, a fuel pressure test will tell you for certain.
Use a good fuel system cleaner while you are at it.
Also check for any loose wires and any battery terminal corrosion, look at the Crankshaft Sensor as well. It can cause these same kinds of indications. I had that experience when my water pump had a pin hole leak and the water dripped on the Crankshaft Sensor causing the same kind "fuel starving" problems to show up. Also ‘96 and later Toyota are OBD2 systems and need a scan tool able to read those kind of codes (check the emissions decal under the hood just to be sure)
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