today i just got dune replacing starter, battery, and the pipes. my ford still chugs(after pulling cats) new gas. im thanking my trany need's a full flush w/new filter. the old owner did replace the throttle body, water pump,full pump,up dated oil change. with a rebuilt trany im hoping its just a fluid/filter issue. if any experts on this are reading this give me your ear...

 

Have you scanned for codes? Checked the fuel pressure (which should be somewhere around 30-40 psi w/eng. running). This engine was not known for the great amounts of power it made, however, it's probably the best engine Ford ever made. It is conceivable that the trans is causing this problem, but a stator problem is rare on these trannies (I haven't seen one in years), but is it starting out in first or second gear? I would always start this diag. to check out engine performance first, due to its very, very large effect on tranmision shifting, etc. Pay attention to the basics also (plugs worn, wires resistive, base and computed timing). Good luck!

 

Fuel pump? Which fuel pump? The HIGH pressure pump on the frame rail or the LOW pressure pump in the tank that feed the HIGH pressure pump? Or both? The 1986-1988 Ranger/Bronco II's Fuel System Requires Two (2) Pumps. (1) In-Tank Low Pressure And (1) In-Line High Pressure. A tired LOW pressure pump will cause the engine to run like a slug. Also was both fuel filters replaced? You have a cartridge type filter element between the tank and the HIGH pressure pump, and then an in-line filter near the HIGH pressure pump.